Mouth Sores in Arthritis Patients

It's not uncommon for arthritis patients to get mouth sores as a side effect from medications. Oral ulcers or mouth sores develop on the palate, under the inside of the lips or inside of the cheeks.

Doctor consulting with patient
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Arthritis medications with mouth sores as a side effect include: 

  • NSAIDs
  • Methotrexate
  • Tumor necrosis factor (TNF) blockers

Your mouth sores may not be a side effect of your arthritis medication. Contact your physician about the side effects you're experiencing so he can determine if a concurrent health condition is responsible.

Why Do NSAIDS Cause Mouth Sores?

Nonsteroidal anti-inflammatory drugs (NSAIDS) such as Motrin (ibuprofen) can increase your risk of getting mouth sores. Researchers from the Research Center at the University of Medicine and Dentistry of New Jersey found NSAIDs impair your body's ability to repair soft oral tissue and heal from oral ulcers. 

Why Does Methotrexate Cause Mouth Sores?

Methotrexate naturally occurs in your body and increasing the levels with medication containing this substance is known to cause mouth ulcers.

A possible side effect of taking prescription methotrexate is mucositis, inflammation of the lining of your mouth. Patients taking high doses are even more susceptible.

Why Do TNF-Blockers Cause Mouth Sores?

It's common to treat rheumatoid arthritis with immunosuppressant medications, including tumor necrosis factor inhibitors because they help suppress your body's inflammation response. Because they suppress your immune system, latent conditions, such as the herpes simplex virus, which causes cold sores, or oral thrush can surface.

Oral thrush is a yeast infection that commonly presents as white patches on the tongue. Rubbing off the white patch reveals a red patch underneath and you might also have an unpleasant taste in your mouth or difficulty swallowing.

Treatments to Help Relieve Mouth Sores

In patients on methotrexate, taking daily folic acid, 1 mg or greater may reduce the incidence of mouth sores. If the problem persists, folinic acid (leucovorin) taken 8-12 hours after methotrexate may help without affecting the efficacy of methotrexate.

In patients who develop mouth sores on NSAIDs, it may help to switch to another NSAID or different therapy. Other treatments which may work to heal or prevent mouth sores include:

  • Supplemental folic acid (have your vitamin B12 checked as increased folic acid may mask occult B12 deficiency)
  • Yogurt
  • Acidophilus

Local steroid therapy such as Kenalog or Orabase may help for a few ulcers, while a combination of dexamethasone/Benadryl/Maalox in a 1/1/1 solution (swish and spit out) may ease the symptoms of multiple ulcers and help to heal.

What Other Arthritis-Related Conditions Cause Mouth Sores?

Many health conditions present with mouth sores as a symptom, including:

  • In Behçet’s (Beh-CHETS or Beh-SHETS) disease, both arthritis and mouth ulcers are symptoms
  • In lupus, both joint pain and oral lesions are symptoms 
  • In vasculitis (an unusual complication of rheumatoid arthritis), mouth ulcers are a symptom
3 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Slomiany BL, Slomiany A. Nonsteroidal anti-inflammatory drugs impair oral mucosal repair by eliciting disturbances in endothelin-converting enzyme-1 and constitutive nitric oxide synthase. J Physiol Pharmacol. 2001;52(1):81-92.

  2. Deeming GM, Collingwood J, Pemberton MN. Methotrexate and oral ulceration. Br Dent J. 2005;198(2):83-5. doi:10.1038/sj.bdj.4811972

  3. Liu L, Liu S, Wang C, et al. Folate Supplementation for Methotrexate Therapy in Patients With Rheumatoid Arthritis: A Systematic Review. J Clin Rheumatol. 2019;25(5):197-202. doi:10.1097/RHU.0000000000000810

Additional Reading
Carol Eustice

By Carol Eustice
Carol Eustice is a writer covering arthritis and chronic illness, who herself has been diagnosed with both rheumatoid arthritis and osteoarthritis.