Mouth Ulcers

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Causes of Mouth Ulcers or Sores

Causes of Canker Sores

Symptoms of Canker Sores

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When to Call Us for Mouth Ulcers

Call 911 Now

  • Not moving or too weak to stand
  • You think your child has a life-threatening emergency

Call Doctor or Seek Care Now

  • Chemical in the mouth could have caused ulcers
  • Dehydration suspected. No urine in more than 8 hours, dark urine, very dry mouth and no tears.
  • Your child looks or acts very sick
  • You think your child needs to be seen, and the problem is urgent

Contact Doctor Within 24 Hours

  • 4 or more ulcers
  • Bloody crusts on the lips
  • Red, swollen and tender gums
  • Ulcers and sores also on the outer lip
  • One ulcer on the gum near a tooth with a toothache
  • Fever or swollen face
  • Large lymph node under the jaw
  • Began after starting a medicine
  • You think your child needs to be seen, but the problem is not urgent

Contact Doctor During Office Hours

  • Cold sores suspected
  • Mouth ulcers last more than 2 weeks
  • You have other questions or concerns

Self Care at Home

  • Canker sores suspected


Care Advice for Mouth Ulcers

What You Should Know About Mouth Ulcers:

  • Canker sores are the most common cause of mouth ulcers.
  • They are 1 - 3 painful, white ulcers of inner cheeks, inner lip or gums (no fever).
  • Causes include injuries from rough food, tooth brushes, biting, or food irritants.
  • Here is some care advice that should help.

Liquid Antacid for Mouth Pain (Age 1 Year and Older):

  • For mouth pain, use a liquid antacid (such as Mylanta or the store brand). Give 4 times per day as needed. After meals often is a good time.
  • Age 1 to 6 years. Put a few drops in the mouth. Can also put it on with a cotton swab.
  • Age over 6 years. Use 1 teaspoon (5 mL) as a mouth wash. Keep it on the ulcers as long as possible. Then can spit it out or swallow it.
  • Can use honey instead, until you can buy a liquid antacid. Follow the same directions as given for antacids. Avoid honey if less than 1 year old.
  • Caution: do not use regular mouth washes, because they sting.

Pain Medicine:

  • To help with the pain, give an acetaminophen product (such as Tylenol).
  • Another choice is an ibuprofen product (such as Advil).
  • Use as needed.

Fluids and Soft Diet :

  • Try to get your child to drink adequate fluids.
  • Goal: keep your child well hydrated.
  • Cold drinks, milk shakes, popsicles, slushes, and sherbet are good choices.
  • Solid Foods. Offer soft, bland foods like macaroni and cheese. Other good ones are mashed potatoes, cereals with milk and ice cream.
  • Avoid foods that need much chewing. Avoid citrus, salty, or spicy foods.
  • Note: fluid intake is more important than eating any solids.
  • For infants, you may need to stop the bottle. Give fluids by cup, spoon or syringe instead. Reason: the nipple can increase the pain.

Return to School:

  • Canker sores cannot be spread to others. Children with canker sores do not need to miss any school.
  • Children with fever need to be checked before going back to school.
  • Also, children with many mouth ulcers should be checked before going back.

What to Expect:

  • They heal up in 1 to 2 weeks on their own.
  • Once they occur, no treatment can shorten the illness.
  • Treatment can help with the pain.

Call Your Doctor If:

  • Mouth ulcers last more than 2 weeks
  • You think your child needs to be seen
  • Your child becomes worse
  • Remember! Contact your doctor if you or your child develop any "Contact Your Doctor" symptoms.

    Disclaimer: this health information is for educational purposes only. You, the reader, assume full responsibility for how you choose to use it.

Canker Sore on Inner Lower Lip

This is a picture of a canker sore on the inner lip. These sores are painful. They can be caused by many things including: injury to the tissue in the mouth, citrus fruits, acidic vegetables and allergic reactions. Some diseases can also cause a canker sore to form.



Cold Sore of Lower Lip

This shows a cold sore on the lip. Cold sores are caused by the Herpes simplex virus. This cold sore has been visible for two days.




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