Confusion, trembling, and pale color are all signs and symptoms of


Hypoglycemia and Low Blood Sugar | Symptoms and Causes

What are the symptoms of hypoglycemia?

While each child may experience symptoms of hypoglycemia differently, the most common include:

  • shakiness
  • dizziness
  • sweating
  • hunger
  • headache
  • irritability
  • pale skin color
  • sudden moodiness or behavior changes, such as crying for no apparent reason
  • clumsy or jerky movements
  • difficulty paying attention or confusion

What causes hypoglycemia?

The vast majority of episodes of hypoglycemia in children and adolescents occur when a child with diabetes takes too much insulin, eats too little, or exercises strenuously or for a prolonged period of time.

For young children who do not have diabetes, hypoglycemia may be caused by:

Single episodes:

  • Stomach flu, or another illness that may cause them to not eat enough
  • fasting for a prolonged period of time
  • prolonged strenuous exercise and lack of food

Recurrent episodes:

  • accelerated starvation, also known as “ketotic hypoglycemia,” a tendency for children without diabetes, or any other known cause of hypoglycemia, to experience repeated hypoglycemic episodes.
  • medications your child may be taking
  • a congenital (present at birth) error in metabolism or unusual disorder such as hypopituitarism or hyperinsulinism.

Beyond F.A.S.T. – Other Symptoms You Should Know

  • Sudden NUMBNESS or weakness of face, arm, or leg, especially on one side of the body
  • Sudden CONFUSION, trouble speaking or understanding speech
  • Sudden TROUBLE SEEING in one or both eyes
  • Sudden TROUBLE WALKING, dizziness, loss of balance or coordination
  • Sudden SEVERE HEADACHE with no known cause

If someone shows any of these symptoms, immediately call 9-1-1 or emergency medical services.

F.A.S.T. is an easy way to remember the sudden signs and symptoms of stroke. Learn more about F.A.S.T.

Warning Signs in Posterior Circulation Strokes

Posterior circulations strokes (a stroke that occurs in the back part of the brain) occurs when a blood vessel in the back part of the brain is blocked causing the death of brain cells (called an infarction) in the area of the blocked blood vessel. This type of stroke can also be caused by a ruptured blood vessel in the back part of the brain. When this type of stroke happens several symptoms occur and they can be very different than the symptoms that occur in the blood circulation to the front part of the brain (called anterior circulation strokes).

Symptoms include:

  • Vertigo, like the room, is spinning.
  • Imbalance
  • One-sided arm or leg weakness.
  • Slurred speech or dysarthria
  • Double vision or other vision problems
  • A headache
  • Nausea and or vomiting

The Mystery of the Inner Shakes

By Dr. Dietrich Haubenberger

As physicians interacting with essential tremor patients and their families, there are several areas where medical research has not yet given us good explanations for, or strategies to manage symptoms that are so commonly reported to us – such as internal tremor. On a regular basis, patients with ET report feeling “internal tremor”, “inner tremor” or the “inner shakes”. Often, it is even hard to separate which tremor is more bothersome, the “external” or visible tremor, or the internal tremor. Internal tremor is frequently described as a quivering movement sensation inside the trunk or inside the limbs, without actual visible movement. This sensation is typically described as being unpleasant, and it may even be the symptom causing the greatest discomfort. It is often difficult to explain, whether the sensation of inner tremor is a feeling in the absence of actual movement, or whether there is actual tremor-movement, which is just too fine to be visibly noticeable.

ET is defined as a tremor of the hands and arms, which can also affect other body areas such as the head, legs, voice, or trunk. In the medical literature, the description of ET – or any other tremor disorder – is focused on the visible shaking of one or more body parts. Therefore, there are many questions that need to be answered in order to understand internal tremor: What do patients with internal tremor experience? How common is internal tremor? Is internal tremor restricted to patients with already existing tremor disorders? Is internal tremor in patients with tremor disorder similar to what patients with anxiety disorders experience as “trembling” sensation, e.g., from fear?

Much more is unknown about internal tremor than what is known. The medical literature is indeed quite sparse when it comes to the research that has been done to find the potential cause(s) of internal tremor. The first and, so far, most detailed report about internal tremor was examining internal tremor in patients with Parkinson’s disease (PD). The goal of this study, which was published 20 years ago, was to answer the questions on how common internal tremor is in patients with PD, the characteristics distinguishing patients with from patients without internal tremor, as well as the features of internal tremor. To answer this question, 100 patients with PD were asked to complete a questionnaire during one of their clinic visits at the Movement Disorders Center of the University of Miami. The results were compared to the questionnaires completed by 50 control subjects without PD. Just under half, 44%, of patients with PD experienced internal tremor, while only 6% in the control group. While slightly more women experienced internal tremor than man (52% vs. 35%), internal tremor was equally present in patients in mild or more severe stages of the disease. Patients with other abnormal sensory symptoms (aching, burning, tingling) were more likely to have internal tremor. While in the group of patients with internal tremor, resting tremor was present slightly more often than in patients without internal tremor (91% vs. 80%), the extent of visible tremor was not associated with a higher likelihood of internal tremor. Internal tremor was felt both in the limb, in the trunk (neck, chest, and/or abdomen), or both in limbs and trunk.

Regarding medication, patients with internal tremor were more likely to be taking anti-anxiety medication as well as the anti-PD drug levodopa. Episodes of internal tremor were usually short: less than five minutes in 28% of patients and less than 30 minutes in 61% of patients. While not 100%, still the majority of patients (64%) reported they noticed internal tremor when they were feeling anxious. And the internal tremor responded in 41% of patients to relaxation or anti-anxiety medication.

While this first research report focused on the symptoms of internal tremor in PD patients, another report studied ET patients as well as patients with tremor related to multiple sclerosis (MS). While the frequency of internal tremor in PD appeared to be lower than in the first study (33%), internal tremor was most common in the group of ET patients. Although the group of ET patients studied was small, six out of 11 ET patients in the study reported symptoms of internal tremor. Due to the small group of study participants, no further comparisons regarding characteristics and features of the symptom were made for ET. In the group of patients with PD and MS, however, internal tremor was associated with visible tremor, as well as anxiety.

What can we learn from these reports? Mainly that internal tremor is present in disorders beyond ET. It is a symptom that is common and therefore should be taken seriously. As a patient experiencing internal tremor, it is important to note these are common symptoms. One central point to take away from the reports on internal tremor is there are likely several causes for internal tremor. Internal tremor can be caused by actual tremor activity in muscles (e.g., of the limbs), which is subtle and not yet visible to the eye of the patient him/herself or the examiner. The association with anxiety in a majority of patients is furthermore an important sign to be recognized, especially as anxiety is more common in ET than in subjects without ET. However, not all patients with internal tremor also suffer from anxiety, therefore internal tremor needs an individualized approach.

It is important that your physician recognize your internal tremor as a real symptom, which can have different potential causes. When physicians initiate therapy for the (visible) tremor, it is important to monitor the response on all presentations of tremor and distinguish between external and internal tremor. If internal tremor is present and possibly also does not respond to tremor-therapy, the doctor may screen for symptoms of anxiety, as this would require a different management approach. Internal tremor may be the first symptom of an otherwise not yet recognized anxiety disorder.

In summary, the recognition of internal tremor as a symptom in tremor patients is a crucial first step for both physicians as well as patients to identify a potential underlying cause, and to eventually select a successful approach for treatment. More research needs to be conducted to identify the individual contributing factors for this clearly common and impairing symptom seen in patients with essential tremor.

Dietrich Haubenberger, MD – Director, Clinical Trials Unit, National Institute of Neurological Disorders and Stroke (NINDS), Intramural Research Program, National Institute of Health (NIH), Bethesda, MD, and member of the IETF’s Medical Advisory Board.

Tremor causes

Tremor is a symptom, rather than a medical condition on its own. Sometimes there is no obvious cause; sometimes it’s a magnification of your normal physiological tremor, brought on by a temporary stimulant such as caffeine or medication.

Among the most common and important causes of tremor are:

Essential tremor

The most common cause of significant, persistent tremor is essential tremor. The medical term for it used to be ‘benign essential tremor’, on the basis that it wouldn’t do you any harm, wouldn’t lead to any other condition and didn’t affect your life expectancy. But for many patients, uncontrollable shaking is anything but harmless. It can make the simplest daily activities a challenge, and has a huge effect on their self-esteem.


Anxiety, like excitement, stimulates release of a hormone called adrenaline, the so-called ‘fight or flight’ hormone. This has profound effects on many parts of your body, mostly aimed at increasing your alertness, muscle strength and ability to run away from danger or turn and face it. Adrenaline stimulates your nerve endings, raising your awareness, and increases the blood flow to the muscles in your arms and legs. Both of these factors make you more likely to tremble. As well as the obvious feeling anxious, anxiety-related tremor is often accompanied by rapid heartbeat (palpitations), shortness of breath, dry mouth and sometimes chest pain.

Low blood sugar

Episodes of low blood sugar, also known as hypoglycaemia or ‘hypos’, are most common if you have diabetes treated with insulin, or type 2 diabetes treatment with sulfonylurea (SU) tablets. SU tablets stimulate your pancreas to produce more insulin, which can drop your blood sugar too low. Other symptoms include sweating, feeling very hungry, irritability, poor concentration, feeling sick, blurred vision and palpitations.


Like adrenaline, caffeine is a stimulant, which raises your level of alertness and stimulates your nerves. While it can be useful for keeping you alert, large quantities of caffeine in a short period can lead to tremorand palpitations.


Culprits include too much salbutamol (used to relieve asthma symptoms); lithium carbonate (usually used in bipolar disorder); some epilepsy medicines; and some cancer treatments. Some antidepressants can also make you feel trembly, especially when you first start them.

Recreational drugs

A variety of recreational drugs including MDMA and amfetamines can lead to tremor and other movement disorders, which may persist after you stop using them.

Alcohol withdrawal

if you’re dependent on alcohol, withdrawal can lead to severe symptoms including shaking, anxiety, confusion, sweating, palpitations and even seizures. This tremor can persist, even weeks after you stop drinking. Alcohol can also damage your brain, including your cerebellum, which is responsible for your balance and co-ordinating your movements. Some people who are dependent on alcohol go through frequent ‘mini-withdrawal’ within hours of their last drink, so they frequently have tremor.

Parkinson’s disease

Tremor is one of the three ‘key features’ of Parkinson’s disease, although it doesn’t always happen. When it does, it tends to affect your hands and arms and it tends to be worse when you’re not moving. The other main symptoms of Parkinson’s disease – slowness of movement and stiffness – may start at about the same time as the tremor, but put may be put down to getting older or general unfitness. Therefore tremor is often the first symptom people bring to a doctor’s attention and this often leads to a diagnosis.

Overactive thyroid

Along with feeling shaky, overactive thyroid can often lead to weight loss despite eating more, anxiety, palpitations, sweating, intolerance to heat, diarrhoea and shortness of breath. You may start off with just one or two symptoms, with more developing over a few weeks.

Multiple sclerosis (MS)

Tremor can be a symptom of MS, but it’s highly unlikely to be the only symptom you get, and other causes are much more likely. In fact, tremor is usually a relatively late symptom, and the average time from diagnosis of MS todeveloping tremor is 11 years

Vitamins and minerals

Vitamin deficiency, particularly of vitamin B1, can lead to tremor. So can Wilson’s disease, an inherited condition in which too much copper builds up in your body. Rare causes like poisoning with arsenic or heavy metals can cause a variety of symptoms including tremor.

How is tremor diagnosed?

Because tremor is a symptom rather than a medical condition, your doctor will concentrate on finding out what is causing your tremor. This is key, because the treatment for tremor depends on what is causing it. They can often narrow down the cause of your tremor by asking key questions. These include:

  • Does your tremor happen when you’re not moving? This sort of ‘rest tremor’ is most often associated with conditions affecting your nervous system, such as Parkinson’s disease or MS. In Parkinson’s disease, the tremor often gets better when you’re moving your limb.
  • Do you get tremor when you try to hold part of your body (usually your arm) out against gravity? This kind of tremor, which can also be brought on by movement, can be due to physiological tremor (which may be exaggerated if your thyroid is overactive or you’re anxious or have drunk a lot of caffeine); by some medications; by certain diseases of the nervous system; and by long-term alcohol misuse.
  • Does your tremor get worse when you try to point at something specific – the closer you get, the wider your aim is from your goal? This is called intention tremor, and may suggest a problem with part of your brain called your cerebellum.
  • Which part or parts of your body are affected by tremor? For instance, essential tremor often starts in one hand or arm, as does the tremor of Parkinson’s disease.
  • Is it there all the time (ie permanently or whenever you carry out a movement that brings it on) or are you sometimes able to sit still, or move around, without any tremor? If it is intermittent, what brings it on (for example, caffeine, when you’re feeling stressed)?
  • Do you have any other symptoms along with your tremor? In about 7 in 10 people diagnosed with Parkinson’s disease, tremor is the first symptom they tell their doctor about.

Tremor treatment

The treatment your doctor suggests will depend very largely on the cause. For instance, if your thyroid gland is overactive, correcting the levels of this hormone in your body should stop your tremor. If you are anxious, your doctor may recommend talking therapy like cognitive behavioural therapy (CBT). If it’s related to medication, changing or reducing the dose of your medication may help, although you should only do this with advice from your doctor. There are lots of alternative medications for treating type 2 diabetes apart from sulfonylureas, which can cause hypos – your doctor can discuss this with you.

Whatever the cause of your tremor, too much caffeine may make it worse. It’s therefore worth thinking about cutting down on your caffeine intake (from tea, coffee, cola drinks and chocolate) or cutting it out altogether. And while alcohol can sometimes improve tremor in the short term, too much alcohol can lead to severe, disabling tremor, as well as other life-threatening complications. As a consequence, doctors never recommend that you ‘self-medicate’ with alcohol.

The possible treatments of essential tremor, the most common cause of tremor, are outlined in detail in the leaflet on essential tremor. Sometimes these treatments are used if you have another kind of tremor, especially if it is having a major impact on your life.

What causes shaky hands?

Updated: November 14, 2018Published: November, 2013

Q . I’ve started to notice a slight shakiness in my writing hand. Is this just normal aging or should I get my shaky hands checked out?

A. If the shakiness is sudden or recent, you should talk to a doctor. It may be nothing serious—for example, just a reversible side effect from a medication or from too much caffeine. However, tremors could be an early sign of a more serious condition, like Parkinson’s disease. In that case, you could benefit from early diagnosis and starting treatment.

The most common form of hand shakiness is known as essential tremor. Its exact cause is uncertain, but essential tremor becomes more common with aging and may run in families. The shakiness in essential tremor is more pronounced with movement, especially when reaching for an object or pouring a drink. Caffeine and anxiety tend to make it worse; drinking alcohol lessens it. A person with essential tremor may notice changes in handwriting, which will appear messy.

Compared with essential tremor, Parkinson’s disease tremor is typically present at rest, moves at a slower rate, and improves with activity. Handwriting may become smaller. In addition, muscle stiffness and problems with walking can accompany Parkinson’s disease.

Essential tremor is not the start of Parkinson’s disease, but sometimes the two conditions can be confused. There are some general differences in the appearance of the tremors, and additional neurologic problems are usually absent in essential tremor. In both conditions, the tremor can worsen over time and medication helps reduce the tremors.

— William Kormos, M.D.
Editor in Chief, Harvard Men’s Health Watch

for a symptom guide on hand tremor. This guide will ask you a series of questions about involuntary hand shaking, trembling, or what is more commonly called tremors.

As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Please note the date of last review on all articles. No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.

Hypoglycaemia (low blood sugar)

If you have diabetes, sticking to your medication plan and eating regular meals can help prevent hypoglycaemia.

It’s also important to monitor your blood glucose levels.

Monitoring blood glucose

Regularly monitoring your blood glucose levels can help you keep your blood glucose as normal and stable as possible, and will help you spot the signs and symptoms of hypoglycaemia quickly.

Your blood glucose level can vary throughout the day, so you may need to check it several times a day, depending on the treatment you’re taking.

You can monitor your blood glucose levels using a blood glucose meter, a small device that measures the concentration of glucose in your blood.

Read more about living with type 1 diabetes and living with type 2 diabetes

Food and alcohol

If you have diabetes, strenuous physical activity can lead to hypoglycaemia. Eating extra carbohydrate-based foods before and during exercise can help reduce the chances of this happening.

If you’re taking insulin, your doctor may advise you to lower your dose before you do strenuous physical activity.

Alcohol can also affect your body’s ability to release glucose. If you have type 1 diabetes, it’s recommended that you drink no more than 2 to 3 units of alcohol a day and eat a snack after drinking alcohol.

Spotting the signs

As hypoglycaemia can develop suddenly, it’s important to be aware of the symptoms of hypoglycaemia so you can treat it quickly. Tell your family and friends about the signs to look out for and let them know how to treat it.

People with diabetes are advised to carry a form of identification with them that states their condition so they can be helped quickly and efficiently.

Keep treatment with you

If you’re at risk of hypoglycaemia, you should carry sugary food and drink with you at all times to treat mild cases as soon as possible.

If you have diabetes, particularly type 1 diabetes, your doctor may recommend medications such as glucose gel to carry with you. This can be used to treat hypoglycaemia that doesn’t respond to normal treatment.

If you’re being treated with insulin, you’ll usually be given a kit that contains an injection of a medication called glucagon. Family members or your carer can be trained to carry out the injection, which should be used if you lose consciousness because of severe hypoglycaemia.

Preventing hypoglycaemia at night

It’s important to avoid recurrent hypoglycaemia during the night (nocturnal hypoglycaemia) as it can reduce the early symptoms of daytime episodes.

If you experience nocturnal hypoglycaemia, you can try:

  • keeping something sugary by your bedside
  • having a snack before bedtime, such as biscuits and milk
  • checking your blood glucose levels between 3am and 4am, when hypoglycaemia is most likely to occur

Hypoglycaemia and driving

As hypoglycaemia can cause confusion, drowsiness, or even unconsciousness, this can present a significant risk to you or other road users.

If you have diabetes that requires treatment with insulin, you must:

  • inform the DVLA and your insurance company
  • test your blood sugar before driving and at regular intervals (at least every two hours) while driving
  • avoid driving if your blood glucose is low
  • avoid driving for 45 minutes after treating hypoglycaemia
  • carry rapid-acting carbohydrates with you in the vehicle at all times

If you experience hypoglycaemia while driving, pull over and stop as soon as it’s safe to do so. Remove the keys from the ignition and get out of the driver’s seat before treating hypoglycaemia in the normal way.

If you have two or more episodes of hypoglycaemia that require assistance in a 12-month period, it’s a legal requirement to stop driving and inform the DVLA.

If you’re a group two driver (you hold a licence to drive buses, coaches or lorries), you’re legally required to stop driving group two vehicles immediately and inform the DVLA if you have a single episode of hypoglycaemia that requires assistance.

Inform your diabetes care team if you start having problems recognising hypoglycaemia or you start to have more regular episodes, even if there were warning symptoms and you were able to treat them without assistance.

See the GOV.UK website for more information about hypoglycaemia and driving

How to Treat Low Blood Sugar: 7 Tricks Every Diabetic Should Know

iStock/Erna Vader

Taking certain diabetes medications, skipping meals, not consuming enough carbs, and even too much exercise can throw your blood sugar off balance and cause low blood sugar. Insomnia and excessive alcohol consumption have also been linked to low glucose levels. When blood sugar dips to a level that’s too low to sustain normal functioning—in most people, that’s below 70 mg/dl—it results in a hypo attack with varying symptoms depending on its severity. People who have recurring bouts of low blood sugar may have no warning signs at all, explains Michael Bergman, MD, endocrinologist and clinical professor of medicine at NYU Langone Medical Center. This is known as hypoglycemic unawareness; the longer you’ve had diabetes, the more common it is. On the milder end of the low blood sugar spectrum, you may feel hungry, nauseated, jittery, nervous, and have cold and clammy-feeling skin. Many people also describe the feeling that their heart is racing or pounding. Low blood sugar can happen at night, too, causing nightmares and night sweats. Moderate low blood sugar can cause behavioral changes, making you fearful, confused, or angry. It can also trigger blurry vision, slurred speech, and problems with balance and walking. A layperson may even mistake you for being drunk. If left untreated, severe low blood sugar can cause loss of consciousness, seizures, irreversible brain or heart damage, coma, or even death. Here are first aid tips to handle a diabetic emergency.

Defeating the Hypoglycemia Binge

By Adam Brown

How to overcome the most frustrating diabetes landmine

The “hypoglycemia binge” is easily one of the most frustrating parts of having diabetes. Upon seeing a “43 mg/dl” on the meter, the chain of events often looks like this: (i) open the fridge or pantry; (ii) EAT, EAT, EAT; and (iii) EAT some more, just to be safe and stop the hunger and shakiness.

Then, a wave of regret hits, followed by a frustrating rebound high blood sugar. In the worst case, I take a “rage bolus” (a term coined by Kerri Sparling), which is often followed by another low blood sugar. The insane part is how easy this is to do repeatedly, since hypoglycemia is so common and so unpleasant in the moment.

The following is the first “Diabetes Landmine” I mention in Bright Spots & Landmines, and it really illustrates the concept – if I can identify my Diabetes Landmines ahead of time, I can build a plan of attack to reduce the chances of stumbling onto them. For hypoglycemia alone, this approach has made an enormous positive difference in my diabetes and quality of life. As noted in the “What Helps Me” section below, setting up an automatic, go-to treatment helps me default to an optimal decision every time – no hypoglycemia-impaired thinking required. Now when I’m low, there is no dangerous pause as I open the fridge and wonder what I’m going to eat; I simply follow my system. Please tell me what you think!

Get all 43 Bright Spots and 16 Landmines here (free PDF) or at Amazon ($6.29 in paperback, $1.99 on Kindle).

Hypoglycemia binge: overeating to correct a low or using it as an excuse to “treat myself”

I consider myself someone with a lot of willpower, but with a blood glucose (BG) of 55 mg/dl, I just want to eat everything in sight. This leads to one of my biggest Diabetes Landmines: overcorrecting a low blood glucose with too many carbs, only to go far too high afterwards.

The picture below is a real example of what I mean – that misfortune occurred after I stormed the fridge at 2 am and corrected a nighttime low using free granola from a friend’s work event. The huge bowl was sitting in our fridge, looked really good, and “I only had a little.” DOH!

I’ve used four strategies to get around this trap, which are all directed at reducing bad impulsive decisions in the moment:

1. Have go-to automatic corrections for hypoglycemia that are quantity limited and unappealing to overeat. Glucose tablets and Smarties are predictable, relieve my low symptoms very quickly, and I know I won’t overeat them. Some of my friends with diabetes count out jelly beans, mini Swedish Fish, gummies, or hard candy – again, allowing them to modify the amount to match exactly what their BG needs.

2. Fill in the blanks:

Eating ___ (amount) of ____ (food) raises my blood sugar by ____ mg/dl.

Example: eating one glucose tab raises my blood sugar by 20 mg/dl.

The only way to discover this is by checking BG, eating a food that has been measured out, and then checking again in roughly 15-30 minutes.

Knowing this helps me adjust the amount of food to raise BG to my target of 100 mg/dl, but not overshoot. Instead of a hypoglycemia binge, it’s more of a precision dose of carbs. If I’m at 60 mg/dl, I know I need only two glucose tabs to get back to 100 mg/dl. If I’m exercising (including walking), have taken bolus insulin within the last three hours (“insulin on board”), or have a down-trending arrow on my CGM, I might add more carbs – glucose will continue to fall, so I need an additional buffer.

3. Do NOT use hypoglycemia as a justification to eat junk. Period. It’s enjoyable and easy to view a low as “treat time,” but I always regret doing so. Plus, it connects a food reward (treat) with something I want to avoid (going low), an easy way to build a bad habit.

4. CGM often has lag time in hypoglycemia; it should not be the only indicator of “I’ve recovered” or “I’m still low and need to eat more.” Continuing to see 60 mg/dl on my CGM encourages overeating correction foods, but often, my BG has recovered (100 mg/dl) and the sensor hasn’t picked it up yet. If I still feel low and want to eat more, I try to confirm a CGM reading 10-20 minutes later with a glucose meter before eating extra correction carbs.

Get all my Bright Spots & Landmines here as a free/name-your-own-price download. You can also purchase it on Amazon in paperback ($6.29) and Kindle ($1.99). The print book is priced at cost to ensure widespread access, and 100% of proceeds from digital downloads benefit The diaTribe Foundation, a 501(c)(3) non-profit.

Have you benefitted from Bright Spots & Landmines? Could you take a few minutes to write a one-sentence Amazon review sharing your experience? It would help us so much!

Have questions, comments, or ideas? Send them here!

Medically reviewed by Last updated on Feb 27, 2019.

  • Health Guide
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What Is It?

Hypoglycemia is an abnormally low level of blood sugar (blood glucose). Because the brain depends on blood sugar as its primary source of energy, hypoglycemia interferes with the brain’s ability to function properly. This can cause dizziness, headache, blurred vision, difficulty concentrating and other neurological symptoms.

Hypoglycemia also triggers the release of body hormones, such as epinephrine and norepinephrine. Your brain relies on these hormones to raise blood sugar levels. The release of these hormones causes additional symptoms of tremor, sweating, rapid heartbeat, anxiety and hunger.

Hypoglycemia is most common in people with diabetes. For a person with diabetes, hypoglycemia occurs because of too high a dose of diabetic medication, especially insulin, or a change in diet or exercise. Insulin and exercise both lower blood sugar and food raises it. Hypoglycemia is common in people who are taking insulin or oral medications that lower blood glucose, especially drugs in the sulfonylurea group (Glyburide and others).

True hypoglycemia with laboratory reports of low blood sugar rarely occurs in people who do not have diabetes. When it does occur outside of diabetes, hypoglycemia can be caused by many different medical problems. A partial list includes:

  • Gastrointestinal surgery, usually involving removal of some part of the stomach. Surgery that removes part of the stomach can alter the normal relationships between digestion and insulin release. “Nissen” surgeries for treatment of gastroesophageal reflux can also result in episodes of hypoglycemia.

  • A pancreatic tumor, called an insulinoma, that secretes insulin

  • A deficiency of growth hormone from the pituitary gland or of cortisol from the adrenal glands. Both of these hormones help to keep blood sugars normal

  • Alcohol

  • Overdose of aspirin

  • Severe liver disease

  • Use of insulin by someone who does not have diabetes

  • Cancers, such as cancer of the liver

  • Rarely, an enzyme defect. Examples of enzymes that help keep blood sugar normal are glucose-6-phosphatase, liver phosphorylase, and pyruvate carboxylase,


Hypoglycemia can cause:

  • Symptoms related to the brain “starving” for sugar — Headache, dizziness, blurred vision, difficulty concentrating, poor coordination, confusion, weakness or fainting, tingling sensations in the lips or hands, confused speech, abnormal behavior, convulsions, loss of consciousness, coma

  • Symptoms related to the release of epinephrine and norepinephrine — Sweating, tremors (feeling shaky), rapid heartbeat, anxiety, hunger


If a person with diabetes has severe hypoglycemia, he or she may not be able to answer the doctor’s questions because of confusion or unconsciousness. In this case, a family member or close friend will need to describe the patient’s medical history and insulin regimen.

To help ensure effective emergency treatment, all people with diabetes should consider wearing a medical alert bracelet or necklace. This potentially lifesaving jewelry will identify the patient as having diabetes, even if the patient is far from home and traveling alone.

Family members or friends of a person with diabetes should learn how to bring a patient out of severe hypoglycemia by giving the person orange juice or another carbohydrate, or by giving an injection of the drug glucagon, which can raise blood sugar.

If a person with diabetes can answer questions appropriately, the doctor will want to know the names and doses of all medications, as well as recent food intake and exercise schedule. If the patient has been self-monitoring blood sugar with a glucometer (a hand-held device to measure glucose levels in blood from a finger prick), the doctor will review the most recent glucometer readings to confirm low blood sugar and to check for a pattern of hypoglycemia related to diet or exercise.

In people who do not have diabetes, the doctor will review current medications and ask about any history of gastrointestinal surgery (especially involving the stomach), liver disease and an enzyme deficit. Patients should describe their symptoms and when the symptoms occur — whether they occur before or after meals, during sleeping or after exercise.

In a person with diabetes, the diagnosis of hypoglycemia is based on symptoms and blood sugar readings. In most cases, no further testing is necessary.

In a person who is not diabetic, the ideal time for diagnostic testing is during an episode of symptoms. At that time, blood can be drawn to measure levels of glucose, and the patient’s reactions to glucose intake can be tested. If these measures confirm the diagnosis of hypoglycemia, blood can be sent to a laboratory to measure insulin levels.

If the patient has no symptoms at the time of evaluation, the doctor may ask him or her to measure his or her blood glucose when hypoglycemic symptoms occur. In non-diabetics, a blood sample can be tested to measure liver function and cortisol levels.

If an insulinoma is suspected, the doctor may order a supervised 48-hour fast. During that period, blood levels of glucose and insulin will be measured whenever symptoms occur or once every six hours, whichever comes first. A blood glucose level of less than 40 milligrams per deciliter with a high level of insulin strongly suggests the person has an insulinoma or has taken insulin or another diabetic drug in secret.

If a person develops symptoms of hypoglycemia only after eating, the doctor may ask him or her to self-monitor blood sugar with a glucometer at the time the symptoms occur.

Expected Duration

An episode of hypoglycemia caused by exercise or by too much short-acting insulin usually can be stopped within minutes by eating or drinking a food or beverage that contains sugar (sugar tablets, candy, orange juice, non-diet soda). Hypoglycemia caused by sulfonylurea or long-acting insulin can take one to two days to go away.

People with diabetes remain at risk for episodes of hypoglycemia throughout life because they need medications that lower blood sugar. Hypoglycemic episodes at night are particularly dangerous because the person often sleeps through part of the time that their blood sugar is low, treating the sugar level less quickly. Over time, repeated episodes can lead to impaired brain function.

About 85% of patients with an insulinoma will be cured of hypoglycemia once the insulin-secreting tumor is removed.

Many people without diabetes who have symptoms that seem like signs of low blood sugar do not truly have low sugar levels. Instead, the symptoms are caused by something other than low blood glucose.


In people taking insulin or other diabetic medicine, drinking alcohol can lead to an episode of hypoglycemia. Patients with diabetes should discuss with their doctors how much alcohol, if any, they can drink safely. Alcohol can cause serious episodes of hypoglycemia even when insulin was taken hours before. People with diabetes should be very aware of this possible problem if they drink.

People with diabetes should always have ready access to emergency supplies for treating unexpected episodes of hypoglycemia. These supplies may include candy, sugar tablets, sugar paste in a tube and/or a glucagon injection kit. A glucagon injection may be given by a knowledgeable family member or friend if a hypoglycemic patient is unconscious and cannot take sugar by mouth. For diabetic children, emergency supplies can be kept in the school nurse’s office.

Any person at risk of hypoglycemic episodes can help to avoid delays in treating attacks by learning about his or her condition and sharing this knowledge with friends and family members. The risk for hypoglycemia is lower if you eat at regular times during the day, never skip meals and maintain a consistent exercise level.

Like people with diabetes, nondiabetic people with hypoglycemia should always have ready access to a source of sugar. In rare circumstances, a doctor may prescribe a glucagon emergency kit for nondiabetic people who have a history of becoming disoriented or losing consciousness from hypoglycemia.


If a conscious person is having symptoms of hypoglycemia, the symptoms usually go away if the person eats or drinks something sweet (sugar tablets, candy, juice, non-diet soda). An unconscious patient can be treated with an immediate injection of glucagon or with intravenous glucose infusions in a hospital.

People with diabetes who have hypoglycemic episodes may need to adjust their medications, especially the insulin dose, change their diet or their exercise habits.

If you recognize that your symptoms are caused by hypoglycemia, you should treat yourself or seek treatment, and not try to just “tough it out.” People with long-standing diabetes may stop experiencing the usual early warning symptoms of hypoglycemia. This is called hypoglycemic unawareness. It can be very serious because the person may not know to seek treatment.

If you and your doctor identify that you are unaware when you have low blood sugars, your dose of insulin or other diabetes medicines will probably will need to be reduced. You will need to check your blood sugar more often. Your insulin dose will likely need frequent adjustments to maintain reasonable blood sugars (but not “perfect” sugars) with less risk of hypoglycemia.

An insulinoma is treated with surgery to remove the tumor. Hypoglycemia caused by problems with the adrenal or pituitary glands is treated by replacing the missing hormones with medication.

Nondiabetic people with hypoglycemic symptoms following meals are treated by modifying their diet. They usually need to eat frequent, small meals and avoid fasting.

When To Call A Professional

Call for emergency medical assistance whenever anyone is unconscious or obviously disoriented. Severe insulin reactions can be fatal, so it is important to seek treatment immediately.

People with diabetes should contact their doctors promptly if they experience frequent episodes of hypoglycemia. They may need to adjust their daily doses of medications, meal plans and/or exercise program.

Nondiabetic people who experience symptoms of hypoglycemia should contact their doctors for evaluation of the problem.


In people with diabetes, the outlook is excellent if they follow their prescribed insulin dosage, recommended diet and exercise guidelines.

Most patients with insulinomas can have them removed successfully by surgery. However, in a small percent of these patients, the insulinoma cannot be completely removed. These patients may still suffer from hypoglycemia after surgery.

Most patients with other forms of hypoglycemia can be treated successfully with changes in diet.

Learn more about Hypoglycemia

Associated drugs

  • Hypoglycemia

Mayo Clinic Reference

  • Hypoglycemia

External resources

National Institute of Diabetes & Digestive & Kidney Disorders
Office of Communications and Public Liaison
Building 31, Room 9A04
31 Center Drive, MSC 2560
Bethesda, MD 20892-2560
Phone: (301) 496-4000

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer

What You Should Know About Shivering

There are many things that can make you shiver. Knowing what can trigger a shiver will help you know how to respond.

Cold environment

When the temperature drops below a level your body finds comfortable, you may start to shiver. Visible shivering can boost your body’s surface heat production by about 500 percent. Shivering can only warm you up for so long, though. After a few hours, your muscles will run out of glucose (sugar) for fuel, and will grow too tired to contract and relax.

Each person has their own temperature at which shivering starts. For example, children without much body fat to insulate them may begin shivering in response to warmer temperatures than an adult with more body fat.

Your sensitivity to cold temperatures can also change with age or because of health concerns. For example, if you have an underactive thyroid (hypothyroidism), you’re more likely to feel cold more acutely than someone without the condition.

Wind or water on your skin or penetrating your clothing can also make you feel colder and lead to shivering.

After anesthesia

You may shiver uncontrollably when anesthesia wears off and you regain consciousness following surgery. It’s not entirely clear why, though it’s likely because your body has cooled considerably. Operating rooms are usually kept cool, and lying still in the cool operating room for an extended period of time can cause your body temperature to decrease.

General anesthesia can also interfere with your body’s normal temperature regulation.

A drop in your blood sugar levels can trigger a shivering response. This can happen if you haven’t eaten for a while. It can also happen if you have a condition that affects your body’s ability to regulate blood sugar, such as diabetes.

Low blood sugar can affect people in different ways. If you don’t shiver or tremble, you may break out in a sweat, feel lightheaded, or develop heart palpitations.


When you shiver, but you don’t feel cold, it could be a sign that your body is starting to fight off a viral or bacterial infection. Just as shivering is your body’s way of warming up on a chilly day, shivering can also heat up your body enough to kill a bacteria or virus that has invaded your system.

Shivering can actually be a step toward developing a fever, too. Fevers are another way your body fights off infections.


Sometimes, shivering has nothing to do with your health or the temperature around you at all. Instead, a spike in your adrenaline level can cause you to shiver. If you’ve ever been so afraid you started trembling, that’s a response to a rapid rise in adrenaline in your bloodstream.


Parkinson’s disease

Other symptoms

Parkinson’s disease can also cause a range of other physical and mental symptoms.

Physical symptoms

  • balance problems – these can make someone with the condition more likely to have a fall and injure themselves
  • loss of sense of smell (anosmia) – sometimes occurs several years before other symptoms develop
  • nerve pain – can cause unpleasant sensations, such as burning, coldness or numbness
  • problems with peeing – such as having to get up frequently during the night to pee or unintentionally peeing (urinary incontinence)
  • constipation
  • an inability to obtain or sustain an erection (erectile dysfunction) in men
  • difficulty becoming sexually aroused and achieving an orgasm (sexual dysfunction) in women
  • dizziness, blurred vision or fainting when moving from a sitting or lying position to a standing one – caused by a sudden drop in blood pressure
  • excessive sweating (hyperhidrosis)
  • swallowing difficulties (dysphagia) – this can lead to malnutrition and dehydration
  • excessive production of saliva (drooling)
  • problems sleeping (insomnia) – this can result in excessive sleepiness during the day

Cognitive and psychiatric symptoms

  • depression and anxiety
  • mild cognitive impairment – slight memory problems and problems with activities that require planning and organisation
  • dementia – a group of symptoms, including more severe memory problems, personality changes, seeing things that are not there (visual hallucinations) and believing things that are not true (delusions)

Feeling Shaky: A Common Sign of Anxiety

At its core, anxiety is essentially long-term stress. Every day you live with anxiety is a day that you’re placing stress on your body, and both anxiety and stress create fairly common symptoms that can hurt your confidence in social situations and make it difficult to complete everyday tasks.

Feeling shaky is a common symptom of anxiety, and one that most people have experienced at some point in their life. It’s sometimes possible for shaking to be the only symptom or one of the first symptoms people notice when they’re feeling nervous. There are ways to reduce the shakiness, but unfortunately, surging adrenaline makes it hard to control completely.

Shakiness is Something You Need to Deal With in Advance

The reality of feeling shaky is that the best way to stop it is with prevention. There are techniques that can reduce anxiety at the moment, but once anxiety hits it’s harder to control than if you never experienced that anxiety in the first place.

So while this article explores anxiety shaking, it helps to remember that anxiety itself is what needs to be controlled the most and with the right treatment the shakiness can go away.

Why Do We Feel Shaky?

During periods of intense nervousness or anxiety, adrenaline/epinephrine is being pumped into the body as the “Fight or Flight” system is activated. It’s the reason that we shake before a big test, or when confronted with a dangerous situation. Your body is essentially preparing to run.

When you suffer from anxiety disorders, your fight/flight system is acting out on its own. You’re receiving these rushes of energy, and your body starts to shake as a result. But because you’re neither fleeing nor fighting, your body simply continues to shake, and that can cause significant distress for those that are trying to maintain their calm.

Are There Different Types of Triggers?

There are different types of triggers. Or, in a way, different types of shaking. Yet all of them may be due to anxiety. Shaking may be caused by:

  • Short-term Anxiety Everyone – even those that don’t have anxiety – can shake when confronted with a situation that causes nervousness. People shake on first dates, they shake before tests, they shake when they have a meeting with their boss; shaking is an incredibly normal experience, but one that is disruptive nonetheless.
  • Generalized Anxiety Disorder (GAD) When someone has GAD, their fight or flight system is firing all throughout the day at low levels, and occasionally can pick up at random times. This may cause shaking to occur for what seems to be no reason, although it tends to be less severe than during times of intense stress.
  • Panic Attacks Before, during, or after panic attacks, shaking can be very common. This type of shaking is absolutely caused by the intense fear that those with panic attacks experience. People with panic attacks may also experience occasionally shaking with no apparent trigger, and that shaking can actually cause a panic attack itself as the person worries that something is wrong.
  • Unexplained Tremor Finally, for reasons that are still unclear, those with day to day anxiety may simply feel shaky or develop a tremor in their hands, feet, etc. It’s not necessarily clear what’s causing this, but long term stress can have unusual effects on your body, and so it should be no surprise that you experience tremor during unusual situations.

There are physical causes of shaking, but these tend to be less common. Also, during periods of stress, the body may deplete important resources, like water or magnesium. Sometimes the body shakes as a result of this nutrient loss. Only a doctor can confirm that you are feeling shaky because of anxiety and not because of some health problem.

What to Do if You’re Shaking

Many people want to stop feeling shaky during periods of anxiety. Feeling shaky makes it hard to show your confidence, and can cause you to feel uncomfortable in many of life’s situations.

Controlling short term shakiness is harder than controlling anxiety in the long term. That’s because once you start shaking, your anxiety is already activated. The only way to stop shaking with certainty is to get out of the anxiety-causing situation, and often that’s not possible. You can’t simply walk out of a first date because you’re nervous, and unless you get comfortable, that shakiness will probably stay until the date is over.

But that doesn’t mean that it’s impossible. Here are some tips to control short term shaking, and afterward we’ll review some of the ways to control long term anxiety:

  • Drink Water Make sure that you’re hydrated. Dehydration can cause shakiness, and many of those with anxiety become dehydrated and allow their shaking to become worse. It won’t stop shaking altogether, but it can be a healthy quick fix.
  • Move It’s not a huge help, but sometimes you simply need to move. If you run in place for a bit, or wiggle your arms around, you may find that some of your shaking is reduced. If you can exercise, that is even better, because exercise has as natural calming effect on the body.
  • Relaxation Techniques There are several relaxation techniques you can try as well. Some of the most common include:
    • Visualization
    • Progressive Muscle Relaxation
    • Deep Breathing
  • Slow Breathing – Hyperventilation can also be a cause of feeling shaky. It often occurs during times of intense anxiety. Solve it by slowing down your breathing. Hyperventilation makes you feel like you’re not getting enough air, but the truth is that you’re getting too much air, so fight the sensation and try to breathe at a slower pace to regain some of the CO2 levels in your body.
  • Body Part Control – Some people find that they can control the shaking if they target each body part one at a time. If your hands are shaking, for example, stare at one hand at a time and see if you can control it. Take deep breaths and move it slowly to make sure that you feel yourself gaining control over the shaking, and then switch to the next hand.

Again, once you start feeling shaky, it’s often hard to control it, because the adrenaline has already been released. You can also try to prevent feeling shaky at these types of events by desensitizing yourself to the fear. For example, if you get anxiety during public speaking, try to schedule public speaking events more often. Eventually they’ll get boring to you, and you won’t shake as much by the time an event matters.

Controlling Long Term Shaking and Anxiety

Shaking caused by anxiety disorders need to be stopped at the source. There are medications and treatments aimed at just stopping the shaking, but these are simply not going to be effective, because every time you have anxiety you run the risk of shaking.

So your goal needs to involve finding some way to stop anxiety permanently. You may not be able to control all shaking from short-term stresses – and you don’t want to, because in general some minor degree of anxiety is actually very healthy – but you do want to be able to reduce the random shaking that you experience from anxiety and panic attacks.

In order to do this, you need to get at the heart of your anxiety. There is more than one type of anxiety, so there is also more than one type of treatment. The most common treatments include:

  • Cognitive Behavioral Therapy
  • Medications
  • Exercise and Anxiety Management
  • Systematic Desensitization and Exposure Therapy

As with most mental health treatments, each person responds differently to each treatment option, and no one method will work for everyone. But anxiety is a 100% manageable condition when you find the right help, and if you are struggling with shakiness – or any anxiety symptom – it is worth it to try multiple treatments to see which one works for you.

Summit Medical Group Web Site

What is anxiety due to a medical condition?

Anxiety is a condition in which you feel nervous, worried, or jittery. You may have panic attacks or feel that something terrible is going to happen. Many medical problems can cause changes in your body that cause anxiety. As your medical condition improves, your anxiety will usually improve. However, if your health remains poor, anxiety may continue.

What is the cause?

The brain makes chemicals that affect thoughts, emotions, and actions. Without the right balance of these chemicals, there may be problems with the way you think, feel, or act. People with anxiety may have too little or too much of some of these chemicals. The balance of chemicals in your body may be upset by medical problems such as:

  • Heart failure or abnormal heart rhythms
  • Brain or nervous system problems such as strokes, Parkinson’s disease, multiple sclerosis, or head injuries
  • Hormone imbalances caused by pituitary, thyroid, or adrenal gland problems, or by diabetes
  • Breathing problems such as shallow, rapid breathing; pneumonia; or chronic lung disease
  • Withdrawal from sedatives or pain medicines

Certain medicines can also cause or worsen anxiety.

What are the symptoms?

Besides feeling nervous and worried, symptoms may include:

  • Thinking that bad things will happen or that you will never get better
  • Having trouble falling asleep or waking up often during the night
  • Having trouble concentrating or remembering things
  • Fearing that you are losing control of yourself and will go crazy or will die
  • Losing weight because you don’t feel like eating, or because your stomach hurts or you have vomiting or diarrhea
  • Having chills, hot flashes, sweating, shaking, numbness, or a pounding heartbeat
  • Having trouble breathing, trouble swallowing, or chest pain

How is it diagnosed?

Your healthcare provider or a mental health therapist will ask about your symptoms, medical and family history, and any medicines you are taking. He will make sure you do not have other medical illnesses or drug or alcohol problems that could cause the symptoms. You may have tests or scans to help make a diagnosis.

How is it treated?

Anxiety can be successfully treated with therapy, medicine, or both. Treating your medical problem can also help reduce anxiety.


Several types of medicines can help. Your healthcare provider will work with you to select the best one for you. You may need to take more than one type of medicine. Before you take any medicine for anxiety, check with your healthcare provider to make sure it is okay to take with the medicines you are taking for your medical problem.


There are several kinds of therapy that can help. Cognitive behavioral therapy (CBT) is a form of therapy that is very effective with anxiety. CBT is a way to help you identify and change thoughts that lead to anxiety. Replacing negative thoughts with more positive ones can help you to control anxiety. Support groups are also helpful.

Other treatments

Claims have been made that certain herbal and dietary products help control anxiety symptoms. Supplements are not tested or standardized and may vary in strengths and effects. They may have side effects and are not always safe. Before you take any supplement, talk with your healthcare provider.

Learning ways to relax may help. Yoga and meditation may also be helpful. You may want to talk with your healthcare provider about using these methods along with medicines and therapy.

How can I take care of myself?

  • Follow your healthcare provider’s instructions and recommended treatment. Keep your follow-up appointments.
  • Get support. Talk with family and friends. Consider joining a support group in your area.
  • Learn to manage stress. Ask for help at home and work when the load is too great to handle. Find ways to relax, for example take up a hobby, listen to music, watch movies, or take walks. Try deep breathing exercises when you feel stressed.
  • Take care of your physical health. Try to get at least 7 to 9 hours of sleep each night. Eat a healthy diet. Limit caffeine. If you smoke, quit. Avoid alcohol and drugs, because they can make your symptoms worse. Exercise according to your healthcare provider’s instructions.
  • Check your medicines. To help prevent problems, tell your healthcare provider and pharmacist about all of the medicines, natural remedies, vitamins, and other supplements that you take. Take all medicines as directed by your provider or therapist. It is very important to take your medicine even when you are feeling and thinking well. Without the medicine, your symptoms may not improve or may get worse. Talk to your provider if you have problems taking your medicine or if the medicines don’t seem to be working.
  • Contact your healthcare provider or therapist if you have any questions or your symptoms seem to be getting worse.

Get emergency care if you or a loved one has serious thoughts of suicide or self-harm, violence, or harming others. Also seek immediate help if you have chest pain or trouble breathing.

For more information, contact:

Back in the 90s, the popular buzz word was hypoglycemia, which means abnormally low blood sugar.
Many of us were feeling pre-meal jitters and/or post-meal stupors, and a number of books and self-help groups blamed hypoglycemia.
But experts finally made it clear that the majority of Americans weren’t dealing with blood sugar that deserves the diagnosis of hypoglycemia, a serious disease. Instead, what we were — and still are — dealing with is something we bring on ourselves, usually by eating a huge meal of simple carbs that seriously spikes our blood sugar.
According to, simple carbohydrates such as candy, cake, nondiet soda and cookies, as well as white bread, bagels and orange juice trigger a spike in blood sugar, so the body then releases insulin to help.
Think of the times you inhaled a box of fudge or ate a big stack of pancakes with lots of syrup. Did you feel shaky afterward?
Bottom line: The higher the sugar intake, the more likely it is that your body will produce excess insulin for the job.
So, the best way to approach the day’s intake of calories is break them up into five or six small meals.
Combine carbs with protein and a little fat such as an egg-white omelet with juice for breakfast, or a dense bread with whole grains and nuts with peanut butter for lunch. Snack on fat-free yogurt or unbuttered popcorn.
Track what you are eating and drinking, as well as the time of day to really see how all this affects your body. Then make adjustments as needed.

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