Sulfasalazine

Pronunciation: pronunciation varies by local usage.

Generic name
Sulfasalazine
Brand names
Azulfidine, Azulfidine EN
Drug class
Aminosalicylate / disease-modifying antirheumatic drug (sulfa-containing)

Availability and supply rules vary by country

Trade names by country: United States · Canada

Australia: · Full directory

What Sulfasalazine is and how it works

Uses, formulations, monitoring, and supply rules can differ by patient, product, and country. Follow the exact local product information and professional advice.

What Sulfasalazine is used for

Ulcerative colitis

Mild to severe disease.

Rheumatoid arthritis

Including polyarticular-course juvenile rheumatoid arthritis.

Before taking Sulfasalazine

Do not take / not appropriate for

  • Do not take sulfasalazine if you are hypersensitive (allergic) to sulfasalazine, to its metabolites, to sulfonamides ("sulfa" medicines), or to salicylates. (all countries)
  • Do not take sulfasalazine if you have an intestinal or urinary obstruction. (all countries)
  • Do not take sulfasalazine if you have porphyria — sulfonamides have been reported to precipitate an acute attack. (all countries)

Tell your clinician about

  • Any allergy to sulfasalazine, sulfonamide ("sulfa") medicines, or salicylates such as aspirin.
  • Any history of intestinal or urinary blockage.
  • Any diagnosis of porphyria.

How to take Sulfasalazine

  • General Instructions: Take sulfasalazine with a full glass of water, after meals or with food, to reduce stomach upset.. Adult Dosing: Ulcerative colitis: typically 3-4 g/day, often started lower to reduce GI upset. Rheumatoid arthritis: typically 2-3 g/day, started low and increased gradually. Exact dose set by your prescriber.. When To Seek Review: Contact your prescriber for unusual bruising, sore throat, fever, or rash.. Storage: Store at room temperature, away from moisture, heat, and light.

Procedures and treatment changes

Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician.

Missed dose

If you miss a dose, contact your prescriber or pharmacist for guidance rather than doubling up.

Overdose

In case of overdose, seek emergency medical attention immediately.

Side effects

Side effects and their urgency vary; report severe, persistent, or concerning symptoms.

Nausea and loss of appetite

What to notice: Common, especially when starting treatment.

What to do: Taking with food and starting at a lower dose can help; contact your prescriber if severe. (2)

Headache

What to notice: A common side effect.

What to do: Contact your prescriber if severe or persistent. (2)

Orange-yellow discoloration of skin, urine, or contact lenses

What to notice: A harmless, expected effect of the medicine’s color.

What to do: No action needed; mention it to your prescriber if it concerns you. (2)

Serious warnings

Sulfa allergy —

Action: Contraindicated if you have a known allergy to sulfonamides (sulfa drugs) or salicylates. Tell your prescriber about any drug allergies before starting.

Blood count problems —

Action: Contact your prescriber promptly for unusual bruising, bleeding, sore throat, fever, or unusual tiredness — blood tests are typically monitored during treatment.

Allergic reaction / severe skin reaction —

Action: Seek immediate medical attention for swelling, difficulty breathing, or a widespread rash.

Interactions

Medicine or testEffectAction
Folic acid absorptionSulfasalazine can reduce folate absorption.Your prescriber may recommend a folic acid supplement. (2)
DigoxinSulfasalazine may reduce digoxin absorption.Your prescriber monitors digoxin levels if combined. (2)

Pregnancy, breastfeeding, kidney/liver function, age

Pregnancy

Requires a primary-source research pass before this section can be completed.

Breastfeeding

Requires a primary-source research pass before this section can be completed.

Children

Frequency: Approved for polyarticular-course juvenile rheumatoid arthritis; dosing set by the treating specialist.. Weight Based: Yes, pediatric dosing is typically weight-based.. Max Daily Dose: Determined by the treating specialist.. Max Single Dose: Determined by the treating specialist.. Age Restrictions: Not recommended in infants under 2 years (risk of kernicterus).

Renal_impairment

Requires a primary-source research pass before this section can be completed.

Hepatic_impairment

Requires a primary-source research pass before this section can be completed.

Monitoring

Storage

Follow the exact product label and keep medicines away from children.

Clinician-facing summary

Clinician-facing context only.

General

Indication: Ulcerative colitis

Dose summary: Ulcerative colitis: typically 3-4 g/day in divided doses, often started lower (1-2 g/day) to reduce GI upset. Rheumatoid arthritis: typically 2-3 g/day, started at 0.5-1 g/day and increased gradually.

Renal context: Use with caution in renal impairment; sulfasalazine and its metabolites are renally cleared. Specific dose-adjustment tables were not found in the sources reviewed — renal function should be assessed by the prescriber before and during treatment. (2)

Frequently asked questions

What is Sulfasalazine used for?

Sulfasalazine (Azulfidine) is used to treat ulcerative colitis and rheumatoid arthritis, including polyarticular-course juvenile rheumatoid arthritis.

What are the side effects of Sulfasalazine?

Common side effects include nausea, headache, and loss of appetite. Sulfasalazine contains a sulfa component and is contraindicated if you have a sulfa allergy. Contact your prescriber promptly for unusual bruising, bleeding, sore throat, fever, or rash — blood counts are usually monitored during treatment.

How should I take Sulfasalazine?

Take sulfasalazine with a full glass of water, after meals or with food, to reduce stomach upset. Typical adult doses are 3-4 g/day for ulcerative colitis or 2-3 g/day for rheumatoid arthritis, usually started at a lower dose and increased gradually by your prescriber.

What is the generic name of Sulfasalazine?

The generic name is Sulfasalazine. It is sold under brand names including Azulfidine, Azulfidine EN.

What class of drug is Sulfasalazine?

Sulfasalazine is classed as: Aminosalicylate / disease-modifying antirheumatic drug (sulfa-containing).

References

  1. · · accessed 2026-08-07 · source 1
  2. Sulfasalazine (Azulfidine) — American College of Rheumatology patient monographDailyMed / authoritative reference · United States · accessed 2026-08-08 · source 2
  3. SULFASALAZINE TABLET [AMERICAN HEALTH PACKAGING] — US prescribing information (DailyMed SPL)U.S. National Library of Medicine (DailyMed) · US · accessed 2026-08-14 · source 3
  4. Sulfasalazine — patient drug information (MedlinePlus)U.S. National Library of Medicine (MedlinePlus) · US · accessed 2026-08-14 · source 4
  5. Sulfasalazine — FDA approval record (Drugs@FDA ANDA080197)U.S. Food and Drug Administration · US · accessed 2026-08-14 · source 5
  6. Sulfasalazine — RxNorm normalized drug concept (RXCUI 9524)U.S. National Library of Medicine (RxNorm) · US · accessed 2026-08-14 · source 6

Brand names by country

Single-ingredient Sulfasalazine names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.

Priority countries

United States

  • Azulfidine EN-tabs500 mg · pfizer laboratories div pfizer inc
  • Azulfidine500 mg · pfizer laboratories div pfizer inc

Canada

  • SALAZOPYRIN
  • SALAZOPYRIN EN-TABS
  • PMS-SULFASALAZINE-E.C.
View brands in additional countries.

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