Thyroid drugs (thyroid hormones) are used to supplement low thyroid levels in people with hypothyroidism.
Hypothyroidism is a condition in which the thyroid gland does not produce enough thyroid hormones to meet the needs of the body. Doctors may use the term “an underactive thyroid gland” to describe hypothyroidism.
Our thyroid gland is a butterfly-shaped gland that is located just below the Adam’s apple, along the front of the windpipe. Even though thyroid hormones are made in the thyroid gland, the production of these hormones is regulated by another hormone, called thyroid stimulating hormone (TSH), which is made by the pituitary gland (a pea-shaped organ found at the base of the brain). If thyroid hormone levels are low, then our metabolism and many other body functions slow down.
Another condition, called hyperthyroidism, is when the thyroid produces too much thyroid hormone. Although hyperthyroidism seems to be the opposite of hypothyroidism, the link between them is complex, and one can lead to the other in certain circumstances.
What are thyroid drugs used for?
Thyroid drugs are used to treat hypothyroidism, also referred to as an underactive thyroid.
Even though the thyroid produces two hormones, T3 and T4, T4 is most commonly prescribed to treat hypothyroidism.
The only way to test for hypothyroidism is with a blood test, as symptoms vary significantly between people and are similar to several other conditions.
Symptoms of hypothyroidism include:
- Cold intolerance
- Decreased sweating
- Dry skin
- Frequent urinary and respiratory tract infections
- Heavy periods
- Joint and muscle pain, cramps, or weakness; slowed movements
- Loss of sex drive
- Puffy face, feet, and hands
- Sleeplessness (insomnia)
- Slowed heart rate
- Thin brittle hair or fingernails
- Tiredness and fatigue
- Weight gain.
If hypothyroidism develops in children or teenagers it may affect their growth; interfere with learning and brain development; and delay tooth development and puberty.
What are the differences between thyroid drugs?
Thyroid hormone preparations can be divided into two categories:
- Natural preparations derived from animal thyroid
- Synthetic preparations manufactured in a laboratory.
Natural preparations include desiccated thyroid and thyroglobulin.
The most common medication used for supplementation is synthetic thyroxine, also called levothyroxine. This is identical to the T4 hormone. T4 is converted into T3 in the body.
Liothyronine (T3, also called triiodothyronine) is another thyroid hormone that may be prescribed to people who are unable to properly convert T4 into T3.
Liotrix is a combination of levothyroxine (T4) and liothyronine (T3) in a 4:1 ratio. Although the ratio remains the same, there are multiple strengths of this medication, so ensure you receive the correct dose.
|Ingredients||Brand name examples|
|levothyroxine||Levoxyl, Synthroid, Tirosint, Unithroid|
|liotrix||Thyrolar-1 (also 1/4, ½, 2,3)|
It is important that levothyroxine is taken on an empty stomach at least 30 to 60 minutes before breakfast to ensure that it is absorbed properly. It should be taken with a big glass of water, and spaced apart by at least four hours from antacids or supplements such as calcium or iron.
Are thyroid drugs safe?
Thyroid medicines are safe when taken at the recommended dose and prescribed by a doctor. You must ONLY take what your doctor recommends. The correct dosage for you is based on your age, health, current natural thyroid hormone levels, and weight.
When you first start treatment for hypothyroidism, your doctor will regularly monitor the levels of different thyroid hormones in your blood to determine if your dosage of thyroid medication needs adjusting. Once the correct dosage has been established for you, the frequency of these blood tests will decrease. Thyroid drugs are generally taken for life.
It will take a few months for your thyroid levels to get back to normal but as long as you are taking your thyroid drugs as prescribed, then you should not have many side effects. Side effects generally happen because you are taking too much thyroid hormone.
Thyroid hormones should NEVER be taken by people without thyroid problems to treat obesity or for weight loss. Some fatalities have occurred when they have been used if these drugs are taken in large dosages for this indication.
Be aware that some supplements marketed as supporting thyroid health may actually contain undisclosed thyroid hormones. Taking these in addition to your thyroid medications may cause toxicity. Thyroid drugs have also been serendipitously added to supplements labeled as only containing animal tissue or herbs such as ashwagandha, guggul, and Coleus forskohlii. Even seaweed-containing products, such as kelp, contain high levels of iodine which can interfere with thyroid function. If you are taking thyroid drugs, always talk with your doctor before taking any supplement.
Also, talk to your doctor about your diet. Some people with hypothyroidism are particularly sensitive to the effects of iodine, and it may trigger or worsen hypothyroidism. In addition, high fiber diets and certain types of foods such as soy or cruciferous vegetables may affect how your body responds to thyroid drugs.
What are the side effects of thyroid drugs?
Thyroid drugs don’t tend to cause side effects if taken at the right dose. Side effects are an indication that you may be taking too much thyroid hormone and may include:
- A fast heartbeat
- Difficulty sleeping
- Dull, lifeless, or brittle hair
- Heat sensitivity
- Nervousness or anxiety
- Weight loss.
If you develop any of these side effects talk to your doctor about a blood test to check your thyroid hormone levels.
Foods to Naturally Support Thyroid Health
Foods to Naturally Support Thyroid Health
By: Laurie Roth-Donnell
Master Herbalist and Holistic Health Practitioner
In hypothyroidism (underactive thyroid), the typical signs include lack of energy, sensitivity to bright light, constipation, irregular periods, chills, hair loss, dry skin, forgetfulness, and weight gain. Many times the body suffers from an over stimulated endocrine system triggered by stress, ingesting stimulants, iodine deficiency, or estrogen dominance, which interfere with proper thyroid function.
The pituitary gland controls the thyroid and adrenal glands, therefore, the nutrients involved in hormone production and regulation of all three glands is particularly important. A combination of vitamins C and B complex, especially B3 and B5, Manganese, Zinc, Selenium and the amino acid Tyrosine (from which Thyroxine is made) all play a role in thyroid health. Caution is to be taken with the supplementation of calcium, magnesium, and potassium, as these are beneficial, but in excess can cause elevated pulse rate and trigger increased thyroid activity. The New Optimum Nutrition Bible recommends avoiding all stimulants, engaging in regular exercise and following supplement therapy: multivitamin, multi-mineral, vitamin C (1,000 mg), Manganese (10 mg), Kelp with Iodine and Tyrosine (2,000 mg- for hypothyroidism only).
The first natural line of defense for mild cases of hypothyroidism is increased exercise and adding iodine sources to your diet (assisting thyroid production of the metabolism-regulating hormones thyroxine (T4) and triiodothyronine (T3)). Dietary supplements containing animal sources of thyroid hormones and nutrients like selenium also support a healthy thyroid. According to Dr. Andrew Weil, one should avoid raw cruciferous plants as they contain phyto-chemicals known as goitrogens (compounds that induce goiter formation by interfering with the synthesis of the hormone produced by the thyroid). The cooking or fermentation process inactivates goitrogen, negating the dangers.
Author Ken Blanchard in What Your Doctor May Not Tell You About Hypothyroidism details foods that may interfere with prescription thyroid medication absorption, as well as, foods that might inhibit T3 production, wherefore should be avoided. His list contains beverages such as caffeinated or decaffeinated drinks and soda pop. He also suggests avoiding fats such as butter, lard, vegetable shortening, peanuts, pine nuts, root or starchy vegetables such as carrots, corn, potatoes, sweet potatoes, and winter squash. Cruciferous vegetables including arugula, broccoli, cauliflower, Brussels sprouts, cabbage, watercress, bok choy, turnip greens, rutabaga, Napa or Chinese cabbage, daikon, horseradish, radishes, kohlrabi, and kale are all goitrogen rich produce. Although these foods are extremely healthful and contain isothiocyanates that break carcinogens down in the body, when ingested uncooked by someone with compromised thyroid function, may further suppress thyroid activity. Blanchard also cautions against eating soy or soy related products including soybeans, soymilk, and protein powder, which have also been shown to suppress thyroid function.
Thyroid friendly foods include beans, water herb teas, olive oil, flaxseed oil, safflower oil, almonds, walnuts, low fat meat, rice, and vegetables (except cruciferous of course). Coconut oil contains lauric acid, which stimulates thyroid function, increasing metabolism and weight loss. I recommend using culinary grade coconut oil when baking and cooking. Dulse, a red algae, is rich in iron and loaded with essential minerals, B vitamins, C, A, and E vitamins and is particularly high in iodine, a metabolic mineral very important for the thyroid gland and brain function. In addition, dulse has the highest frequency of all essential minerals, acts as a controller for calcium metabolism, and protects the brain by destroying toxins in the blood before they pass through the blood-brain barrier. Dulse can be purchased in a powder form and added to your favorite smoothie. Natural sources of iodine include sea foods such as bass, cod, halibut, perch, pike, red snapper, shad, sole, sturgeon, swordfish, tilefish, rainbow trout, and yellowtail. All great sources of natural iodine.
The incident of mild hypothyroidism in the United States is estimated at thirty percent in women. Many women, later in life, commonly confuse the symptoms of thyroid malfunction with those of menopause, going years without a proper diagnosis and treatment plan. In order to monitor your thyroid health, testing after the age of 35 is recommended. Please visit your primary care physician regarding testing and treatment options if you are experiencing any symptoms of thyroid over or under activity.
Dr. Andrew Weil, (http://www.drweil.com)
The New Optimum Nutrition Bible, by Patrick Holford
What Your Doctor May not Tell You about Hypothyroidism, by Ken Blanchard
Synthroid contains levothyroxine sodium, a substance identical to the thyroid gland hormone. It is used either alone or in combination with diet pills to treat primary (thyroidal), secondary (pituitary), tertiary (hypothalamic) hypothyroidism, subclinical hypothyroidism, and obesity.
Dosage and direction
The dose is be administered individually. Follow all recommendations of your doctor, do not exceed the recommended dose. Take it as a single daily dose 0.5-1.0 hour before breakfast with a full glass of water. Intake of Levothroid and the medications known to interfere with its absorption should be separated by at least four hours. Do not stop treatment without permission of your doctor even if you do not feel immediate effect. It may take several weeks till the medication starts to act. Yo may need Levothroid till the end of your life to replace the thyroid hormone deficit.
Cautiousness should be exercised in treatment of the patients with cardiovascular disease, elderly, individuals with concomitant adrenal insufficiency.
Synthroid cannot be used in patients with untreated subclinical or overt thyrotoxicosis, acute myocardial infarction, and uncorrected adrenal insufficiency.
Possible side effect
The most likely adverse reactions to occur are headache, insomnia, nervous or irritable feeling, hyperactivity, anxiety, emotional lability, fever, tachycardia, arrhythmias, hot flashes, sweating, changes in your menstrual periods, appetite changes, diarrhea, vomiting, weight changes, hair loss, flushing.
Inform your doctor about all medications, herbal products and food supplements you use and especially about calcium carbonate (Oystercal, Caltrate, Citracal), sodium polystyrene sulfonate (Kayexalate, Kionex), ferrous sulfate iron supplement, sucralfate (Carafate), antacids that contain aluminum (Rulox, Tums, Maalox, Mylanta, Riopan, Amphojel, Gaviscon), cholesterol-lowering drugs colestipol (Colestid) and cholestyramine (Questran), warfarin, digoxin, estrogen products, diabetes medicines, amiodarone, iodide, lithium, anti-thyroid agents, phenobarbital, rifamycins, beta blockers, antidepressants and growth hormones.
If you missed a dose take it as soon as you remember, but not if it is almost time of the next intake by your schedule. Skip the missed dose if it is almost time of your next dose. Do not try to compensate a missed dose by taking an extra one.
Overdose symptoms include pounding heartbeat, chest pain, tremor, leg cramps, confusion and disorientation, shortness of breath, vomiting, diarrhea, or seizures. Contact your doctor on emergency if you experience them.
Store at room temperature between 59-77 F (15-25 C) away from light and moisture, kids and pets. Do not use after expiration term.
We provide only general information about medications which does not cover all directions, possible drug integrations, or precautions. Information at the site cannot be used for self-treatment and self-diagnosis. Any specific instructions for a particular patient should be agreed with your health care adviser or doctor in charge of the case. We disclaim reliability of this information and mistakes it could contain. We are not responsible for any direct, indirect, special or other indirect damage as a result of any use of the information on this site and also for consequences of self-treatment.