Expert Q&A: Mouth Sores with RA

Question: Why do I get mouth sores? Are they related to my RA?

Answer: Mouth sores can have many different causes, some of which may be related to your RA or its treatment. One of the most common causes of mouth sores in patients with RA is treatment with methotrexate.  Fortunately, taking a folic acid supplement along with methotrexate can help prevent this and other side effects of the drug. Other common causes of mouth sores include infections such as the oral herpes virus and the Candida fungus. The herpes virus causes cold sores or fever blisters, tiny fluid-filled blisters on or around the lips. Overgrowth of the Candida fungus causes oral thrush, characterized by painful white bumps on the tongue, tonsils and insides of the cheeks. While these infections are not directly related to RA, if you are taking medications for RA that suppress your immune system, they are more likely to take hold. Some of those most common mouth sores include small shallow lesions called canker sores and sores caused by irritation from poorly fitting dentures, braces or a broken tooth, for example. These are not related to arthritis. I would recommend speaking with your rheumatologist and dentist, who can help determine the cause of your frequent mouth sores and the best way to treat them.

Debendra Pattanaik, MD

Associate Professor, Medicine-Rheumatology

University of Tennessee Health Science Center, Memphis