Patients should consult their physician before taking any additional prescriptions, over-the-counter medications, nutritional supplements or herbal medications. Patients should not take aminosalicylates if they are allergic or otherwise sensitive to salicylates (such as aspirin).

Patients also should not use sulfasalazine if they are allergic or otherwise sensitive to drugs containing sulfur, such as thiazides (blood pressure drugs), furosemide (drug that reduces swelling and water retention) or sulfonylureas (antidiabetic drugs). Antacids may increase the body’s ability to absorb sulfasalazine, raising the risk of toxicity. Use of sulfasalazine may also reduce gastrointestinal absorption of drugs such as digoxin (heart drug) and folic acid (used to treat deficiency of the B vitamin).