Many drug interactions with disease-modifying antirheumatic drugs (DMARDs) exist. Patients are encouraged to consult a physician before taking any additional prescriptions, over-the-counter medications, nutritional supplements or herbal medications.

Patients are advised to discuss with a physician whether vaccines should be administered when taking DMARDs. In addition, several DMARDs may cause an increase in sun sensitivity. Eating grapefruit or drinking the juice should be avoided before or after taking the DMARD cyclosporine. Recent research also suggests that pomegranate juice may affect some medications like grapefruit juice does. Use of antacids at the same time as sulfasalazine is not recommended.

Some types of medication may reduce the effectiveness or cause side effects in patients taking DMARDs, depending on the situation of the patient. They include:

• Antibiotics, antifungals and antivirals
• Anticonvulsants
• Birth control pills (oral contraceptives)
• Heart medications
• NSAIDs, including aspirin, ibuprofen and naproxen
• Tuberculosis drugs

Blood pressure, kidney function and liver function are often monitored regularly to protect against side effects. Long-term DMARD therapy in children and pregnant women is usually discouraged. In addition, DMARDs may not be appropriate for patients who have recently undergone radiation therapy.