Canker sores, or aphthous ulcers, are small sores on the inside of the mouth. They can occur in both men and women of any age, but they’re more common in women and in people between the ages of 10 and 40. Around 20 percent of the population get these types of sores, according to the National Institutes of Health (NIH). Canker sores are usually very painful, but are benign and are not contagious.
- Types & symptoms
- Treatment & medications
- Canker sores — TheFamily Health Guide
- Canker sores
- Complex Canker Sores: What They Are and How They’re Treated
- Causes of Complex Canker Sores
- Prevention and Treatment
- Canker Sores
- What are canker sores?
- What are the symptoms of canker sores?
- What causes canker sores?
- What are the risk factors for canker sores?
- How are canker sores treated?
- What are the potential complications of canker sores?
- Canker Sores
- Symptoms and Signs of Tonsillitis Symptoms, Causes, Treatments, and Home Remedies
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Types & symptoms
There are three types of canker sores: minor, major and herpetiform. Minor canker sores are the most common and are a half-inch (12 mm) in diameter and oval shaped, according to the Mayo Clinic. The pain usually goes away in a few days and the sores completely clear up without scarring in one to two weeks, without the need for medication.
Major canker sores are bigger than a half-inch in diameter and have irregular edges, according to the Mayo Clinic. They can take up to six weeks to heal and can leave scars.
Herpetiform canker sores, are a less common form of sore. It usually forms in older people and appear in clusters of 10 to 100. The sores are no bigger than one-eighth of an inch (3 mm) in diameter, have irregular edges and heal in one to two weeks.
Along with all three types of canker sores, it’s not uncommon to experience fever, swollen lymph nodes or listlessness as additional symptoms. A person may feel a tingling in the mouth before the sore appears.
Canker sores are commonly mistaken for cold sores, but the two conditions are very different. One way to distinguish between a cold sore and a canker sore is by location. While canker sores always occur inside the mouth, cold sores do not. “An outbreak generally causes small blisters or sores around the mouth, and they heal within a couple of weeks,” said Dr. Alan Mensch, senior vice president of medical affairs at North Shore-Long Island Jewish’s Plainview and Syosset hospitals.
There is no single cause for canker sores, according to the National Library of Medicine. Many are caused from minor injury to the inside of the mouth, whether from accidentally biting the tongue or cheek, an injury from dental work, eating overly spicy or acidic foods or overzealous teeth cleaning. Hormone changes, food allergies, autoimmune conditions, viral infections and possibly genetics may cause these types of sores, as well.
Several studies have found that there is a genetic connection and those with a family history are more likely to have more severe sores, according to the National Library of Medicine. For example, one study published in the journal Oral Surgery, Oral Medicine, Oral Pathology Oral Radiology and Endodontics in 1977 focused on 19 sets of twins and 318 individuals from six families and found that those in the study with a family history are more likely to have canker sores.
Sores are also linked to stress — more prevalent during high-anxiety moments — as well as a women’s menstrual cycle, which is why they tend to be more common in women, according to Nemours Center for Children’s Health Media.
Toothpastes and mouthwashes that contain sodium lauryl sulfate are also potential causes for canker sores. In addition, bacteria Heliobacter pylori, which cause peptic ulcers in the stomach; having an intestinal disorder such as Celiac disease, an inflammatory bowel disease; or the inflammatory disorder Behcet’s disease are also potential causes for canker sores.
Treatment & medications
Most canker sores clear up on their own, but there are some over-the-counter remedies that contain ingredients like carbamide peroxide, menthol, eucalyptus and benzocaine that can help relieve pain, according to Nemours.
A medical professional should be contacted if:
- The person has a high fever
- The sores are spreading
- The sores are unusually large
- The sores have lasted three weeks or longer
- There is severe pain, even when taking over-the-counter pain medication
- The person isn’t able to drink enough fluids
Oral rinses that contain dexamesathone may be prescribed for serious canker sores, according to the Mayo Clinic, as well as topical pastes that contain benzocaine (known as Orabase), amlexanox (known as Aphthasol) and fluocinonide (known as Lidex and Vanos). Debacterol is another topical treatment that chemically cauterizes the sores and reduces healing time.
There are a number of common home remedies that work, too. Gargling with salt water helps to relieve pain, according to the NIH. Dabbing the sore with a mixture of half water, half hydrogen peroxide, followed by a dab of Milk of Magnesia a few times a day soothes and can help speed the healing process. Swishing and then spitting a mixture of half liquid Benadryl and half Milk of Magnesia can also help, according to the NIH.
Because canker sores are also linked to a diet low in folic acid, thiamine (vitamin B1), zinc, vitamin B12 or iron, a doctor might also prescribe nutritional supplements. Symptoms of mild niacin deficiency canker sores, as well, according to the University of Maryland Medical Center.
It isn’t possible to completely prevent canker sores, but it is possible to minimize their prevalence by not eating fried, crunchy, acidic or spicy foods that can irritate the mouth, according to the Mayo Clinic. Also, healthy oral hygiene and avoiding talking while eating are ways of preventing a sore from happening.
- U.S. National Library of Medicine: Overview-Canker Sores
- Cleveland Clinic: Canker Sores & Dental Health
- American Academy of Oral Medicine: Canker Sores – Treatment
Canker sores — TheFamily Health Guide
Published: February, 2005
Most people have been bothered at one time or another by canker sores. Doctors call them aphthous ulcers, but the name doesn’t explain the problem. In fact, physicians and dentists don’t know what causes cankers, though many have tried to find out. Scientists have learned that they are not caused by herpes or any other known virus and that they are not contagious. And with rare exceptions, cankers are isolated problems that crop up in healthy people without indicating a serious medical condition.
Cankers are shallow ulcers that can develop on the inside of the cheek or lips or under the tongue. Most are pink or reddish, but some have a white coating. They are painful, so they make eating a chore, but they almost always clear up in about a week.
If you are one of the very few people who develop fever, swollen glands, weakness, eye or joint inflammation, abdominal cramps and diarrhea, or genital ulcers along with your cankers, you should see your physician. In the vast majority of cases, however, medical attention is not needed. You can simply wait it out: Avoid foods that trigger pain, and use a mild over-the-counter pain reliever if necessary. You can also make a soothing mouthwash by mixing equal parts of Milk of Magnesia and Benadryl Allergy liquid. Swish a teaspoon of the mixture in your mouth for 30–60 seconds, then spit it out. If it seems to help, you can repeat the rinse every four hours. For stronger relief, your physician or dentist can prescribe a local anesthetic such as benzocaine (Orabase-B) or lidocaine (Xylocaine Viscous). Use a Q-tip to paint the anesthetic on the sore 30 minutes before meals and as otherwise needed.
Although it’s small comfort when your mouth hurts, keep in mind that up to half of all adults have experienced canker sores at least once.
February 2005 Update
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Complex Canker Sores: What They Are and How They’re Treated
Almost everyone’s had a canker sore before: those annoying, painful little sores that sometimes result from eating too much acidic food or accidentally biting the inside of your cheek. But for some people, canker sores are a serious problem. Complex canker sores can last for weeks and even leave scars. If you have a canker sore that’s more than just a minor annoyance, it’s best to educate yourself before seeing your health care provider about treatment and prevention options.
Regular vs. Complex
Regular canker sores are annoying and can make eating painful, but they usually heal by themselves in seven to ten days. Complex canker sores, according to the Cleveland Clinic, are much larger than the usual sore and can last up to a month. They are painful and sometimes debilitating. While regular canker sores result from stress, mouth abrasions or acidic food, the complex variety are typically a symptom of an underlying health issue. Complex sores can also have other symptoms, such as fever, swollen lymph nodes and sluggishness.
Causes of Complex Canker Sores
The severity of complex sores suggests that there might be another problem in play. Some of the health issues and diseases that can cause complex sores are:
- Behcet’s disease
- Crohn’s disease
- Autoimmune deficiencies and diseases
- Vitamin deficiency
- Viral infections
Prevention and Treatment
The most important way to prevent complex canker sores is first and foremost to ask your health care provider about the health issues that can cause them. Treating these underlying issues may help you prevent complex canker sores altogether.
If you currently have a complex sore, the National Center for Biotechnology Information suggests trying one of these over-the-counter treatments:
- Analgesics and anesthetics. Analgesics are numbing products that contain medicines like benzocaine and help relieve the pain for a short time. Analgesics typically come in liquid and gel forms, which can be washed away by saliva. Make sure to always follow product package instructions on application frequency.
- Occlusives. These are protective films that adhere over the sore to guard it during the healing process. They’re available at most drugstores and typically last longer than analgesic medicines.
- Antiseptics. Antiseptics use ingredients like sodium bicarbonate (baking soda) or hydrogen peroxide to speed healing by killing excess bacteria around the sore.
- Nonsteroidal anti-inflammatory drugs. Taking OTC pain relievers like ibuprofen or acetaminophen may alleviate the swelling and pain associated with canker sores. Make sure to follow package instructions and only take as directed.
If your canker sores are especially severe, your doctor might suggest taking prescription medications, such as antibiotics, to treat any accompanying infection. They also might recommend taking corticosteroids to reduce swelling and help heal your sores.
Complex sores can disrupt your life and make activities like eating and talking extremely painful for weeks. Since they’re usually the symptom of something more serious, it’s important to make an appointment with your health care provider to explore and diagnose the true reasons for these sores. A treatment plan can help you prevent the painful problem and finally find relief.
What are canker sores?
Canker sore is the name for a painful, open sore in the mouth that is medically known as aphthous ulcer. The sores are not contagious and are small, shallow lesions that develop on the soft tissues in the mouth and gums.
Canker sores are more common in women than men. Most commonly, canker sores first appear between the ages of 10 and 40. Canker sores may result from mouth injury, viral infections, hormonal shifts, an abnormal immune system, or a diet low in nutrients.
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Signs and symptoms of canker sores can last for about one week. The disease course varies among individuals. Some people with canker sores have one painful red spot that develops into an open ulcer that is usually white or yellow, while others may have swollen lymph nodes, fever, and more than one canker sore at a time. Fortunately, you can treat canker sores successfully with over-the-counter remedies to reduce pain. Even better, you can reduce your risk of canker sores by carefully brushing your teeth so as not to injure your mouth, eating a nutritious diet, and reducing stress.
Seek immediate medical care (call 911) for serious symptoms such as high fever (higher than 101 degrees Fahrenheit) and difficulty swallowing or breathing.
Seek prompt medical care if you are being treated for canker sores but mild symptoms recur or are persistent.
What are the symptoms of canker sores?
Canker sores cause a local area of inflammation in the mouth that may result in a number of symptoms. The symptoms can vary in intensity among individuals.
Common symptoms of canker sores
The most common symptoms of canker sores are found in the mouth and include:
- Red spot or bump that develops into an open ulcer
- Single bump or group of bumps
- Sore that heals without scarring in one to two weeks
- White or yellow center ulcer
Less common symptoms of canker sores
Less common symptoms of canker sores are related to a more severe form and include:
- Clusters of sores
- Extensive scarring
- Sore greater than 0.5 inch, or 12 mm, in diameter
- Sore with irregular edges
- Swollen lymph nodes
Symptoms that might indicate a serious condition
In some cases, canker sores can be a serious condition that should be evaluated immediately in an emergency setting. Seek prompt medical care if you, or someone you are with, have any of these serious symptoms including:
- Difficulty swallowing or breathing
- Extreme difficulty eating or drinking
- High fever (higher than 101 degrees Fahrenheit)
What causes canker sores?
A variety of factors can cause canker sores, including injury during tooth brushing, dental work, trauma or emotional stress, hormonal changes, spicy foods, and nutrient deficiencies. The sores occur commonly with viral infections. In some cases, the cause cannot be identified.
Common causes of canker sores
It is not always possible to determine what caused a canker sore. The most common causes of canker sore include:
Minor injuries during tooth brushing or dental work
Toothpastes and mouth rinses containing sodium lauryl sulfate
Disease causes of canker sores
Canker sores can also be associated with certain diseases including:
Autoimmune diseases such as lupus
Behcet’s syndrome (a disease characterized by widespread inflammation of blood vessels)
Crohn’s disease (inflammatory bowel disease that can affect any part of the intestine), ulcerative colitis, and other inflammatory bowel diseases
What are the risk factors for canker sores?
A number of factors increase the risk of developing canker sores. Not all people with risk factors will get canker sores. Risk factors for canker sores include:
Abnormal immune system
Biting your cheek or tongue
How are canker sores treated?
Treatment for canker sores does not normally require medical care from your health care provider unless the symptoms cause you concern or are persistent. If you experience more than three canker sores in one year you should contact your health care provider.
Over-the-counter anesthetics and antimicrobial mouth rinses are the mainstay of treatment for canker sores and can be highly effective. If you receive medical care, it is important to follow your treatment plan for canker sores precisely and to follow instructions carefully to enhance recovery.
Treatments for canker sores
Preparations that are effective in the treatment of canker sores include:
Baking soda paste
Mouth rinses, such as salt water, baking soda (dissolve 1 teaspoon of soda in 1/2 cup warm water), hydrogen peroxide diluted by half with water, or a mixture of 1 part diphenhydramine (Benadryl) to either 1 part bismuth subsalicylate (Kaopectate) or 1 part simethicone (Maalox)
Milk of magnesia placed directly on the canker sore
Numbing agents, such as benzocaine (Anbesol, Orajel), ice, or ice chips
What you can do to improve your canker sores
In addition to following your health care provider’s instructions and taking all medications as prescribed, you can speed your recovery by:
Avoiding hot, spicy or acidic foods that can irritate the sore
Brushing teeth gently, using a soft brush
Placing oral bandages on ulcers
Seeing your dentist if the sores do not heal or are painful
What are the potential complications of canker sores?
You can help minimize your risk of serious complications by following the treatment plan you and your health care professional design specifically for you. Complications of canker sores include:
Candida infection in the mouth (thrush)
Cellulitis or Ludwig’s angina (bacterial infections)
Canker sores show up inside the mouth, unlike cold sores.
What are canker sores?
Canker sores are small shallow ulcers that occur in the lining of the mouth. The medical term for canker sores is “aphthous ulcers.” Canker sores start as white to yellowish ulcers that are surrounded by redness. They are usually very small (less than 1 mm) but may enlarge to ½ to 1 inch in diameter. Canker sores can be painful and often make eating and talking uncomfortable. There are two types of canker sores:
- Simple canker sores: These may appear 3 or 4 times a year and last up to a week. Anyone can get canker sores. However, canker sores typically occur in people between 10 and 20 years of age.
- Complex canker sores: These are less common and occur more often in the people who have previously had them.
What causes canker sores?
The exact cause of most canker sores is unknown. A stress or minor injury to the inside of the mouth is thought to be the cause of simple canker sores. Certain foods —including citrus or acidic fruits and vegetables (such as lemons, oranges, pineapples, apples, figs, tomatoes, strawberries) — can trigger a canker sore or make the problem worse. Use of nonsteroidal anti-inflammatory drugs, like ibuprofen (Advil®, Motrin®), is another common cause. Sometimes a sharp tooth surface or dental appliance, such as braces or ill-fitting dentures, might also trigger the sores.
Some cases of complex canker sores are seen in patients with diseases of the immune system. These diseases include lupus, Behcet’s disease, inflammatory bowel diseases (including celiac disease, ulcerative colitis and Crohn’s disease) and AIDS. Canker sores are also seen in patients with nutritional problems, such as a deficiency in vitamin B-12, zinc, folic acid or iron.
What are the symptoms of canker sores?
You may have a canker sore if you have:
- A painful sore or sores inside your mouth — on the tongue, soft palate (the back portion of the roof of your mouth) or inside your cheeks
- A tingling or burning sensation prior to the appearance of the sores
- Sores in your mouth that are round, white, or gray in color, with a red edge or border
In severe attacks, you may also experience:
- Physical sluggishness
- Swollen lymph nodes
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Symptoms and Signs of Tonsillitis Symptoms, Causes, Treatments, and Home Remedies
Doctor’s Notes on Tonsillitis Symptoms, Causes, Treatments, and Home Remedies
Tonsillitis refers to inflammation of the tonsils in the back of the throat. Acute tonsillitis refers to a short-term illness and is caused by infections with a number of different bacteria or viruses. Infectious mononucleosis (“mono”) and strep throat are two examples of acute tonsillitis. Chronic, or long-term, tonsillitis is a persistent infection of the tonsils that can eventually lead to stone formation within the tonsils.
Symptoms of tonsillitis include a painful sore throat that can cause pain with swallowing or difficulty swallowing. Associated signs and symptoms can include fever, nasal congestion, runny nose, bad breath, swollen lymph nodes in the neck, loss of voice or hoarseness, and headache. The tonsils themselves may be enlarged, red, swollen, and may be covered with white patches or pus.
Medical Author: Melissa Conrad Stöppler, MD, Chief Medical Editor Medically Reviewed on 3/11/2019
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