Taking Sulfasalazine (Azulfidine) for Arthritis

Sulfasalazine (brand name Azulfidine) is a drug that has been available for about 60 years, but its use only increased within the last two decades. It did seem to lose some popularity as biologic drugs were first marketed in 1998 for rheumatoid arthritis. It seems to be making a comeback for patients who cannot tolerate methotrexate or who are unsuitable candidates for biologic drugs.

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Drug Class

Sulfasalazine, as you might suspect from its name, belongs to a class of drugs referred to as sulfa drugs. Sulfasalazine contains salicylate and the sulfa antibiotic. Sulfasalazine is also classified as a DMARD (disease-modifying antirheumatic drug).

Indications for Use of Sulfasalazine

Aside from its use as a treatment for rheumatoid arthritis, sulfasalazine is also prescribed for juvenile arthritis, psoriatic arthritis, ankylosing spondylitis, and ulcerative colitis.

Sulfasalazine helps reduce pain, swelling, and stiffness associated with arthritis. It is most effective for treating mild to moderate symptoms. Sulfasalazine also may prevent joint damage and decrease the risk of reduced joint function. Typically, patients who respond to sulfasalazine notice improvement within 12 weeks.

Dosing Information and Availability

Sulfasalazine is available as a 500 mg tablet. It is recommended that you partake of some food and drink a full glass of water when ingesting sulfasalazine. Treatment for rheumatoid arthritis typically starts gradually. For the first week, patients take 1 or 2 sulfasalazine tablets per day. It may then be increased to two tablets twice a day. The maximum dose is 6 tablets per day. Enteric-coated tablets are available and may help with stomach upset.

Common Side Effects

Sulfasalazine is associated with few common side effects. The most common side effects are nausea or abdominal discomfort. Abdominal issues seem to resolve over time, especially when the drug is given at a low dose initially. Less common side effects may include skin rash, headache, mouth sores, itching, problems with liver function, and sun sensitivity.

Possible Severe Adverse Reactions

Severe adverse reactions associated with sulfasalazine include anorexia, severe headache, severe gastric distress, vomiting, and low sperm count. The low sperm count may be reversible with discontinuation of the drug. These adverse reactions affect about one-third of patients treated with sulfasalazine. Adverse reactions that affect no more than 1 in 30 patients taking sulfasalazine include itching, hives, fever, Heinz body anemia, hemolytic anemia, and cyanosis (bluish discoloration).​​​​

While severe adverse reactions are not considered common, they do tend to increase when the daily dose of sulfasalazine equals or exceeds 4 grams. Also, there are other adverse reactions associated with sulfonamides (sulfa drugs) that must be considered possible with sulfasalazine, including blood disorders, hypersensitivity reactions, central nervous system reactions, renal reactions, and urine and skin discoloration.

Contraindications (Who Should Not Take the Drug)

Sulfasalazine is not an appropriate treatment option for patients with intestinal or urinary obstruction, porphyria, or in patients with known hypersensitivity to sulfasalazine, sulfonamides, or salicylates.

Warnings and Precautions

To minimize the risk of side effects or adverse reactions. you should be aware of the following warnings and precautions while taking sulfasalazine.

  • Regular blood tests should be performed to monitor blood counts, kidney function, and liver function.
  • If you are planning to become pregnant, you are encouraged to discuss sulfasalazine usage with your doctor. Women who are breastfeeding should not take sulfasalazine.
  • Folic acid supplementation may be necessary if you are being treated with sulfasalazine.
  • Be aware of possible drug interactions with sulfasalazine if you also take Coumadin (warfarin), cyclosporine, or digoxin. The drug may increase the risk of liver injury in patients who take isoniazid for tuberculosis. Sulfasalazine may also increase the risk of low blood sugar among patients who take some diabetes medications.
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Article Sources
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  • Sulfasalazine (Azulfidine). American College of Rheumatology. March 2015.

  • Rheumatoid Arthritis: Early Diagnosis and Treatment. Cush JJ M.D., Weinblatt ME M.D., Kavanaugh A M.D. Professional Communications, Inc. Third Edition. Copyright 2010.