Schedule H

Oral

• Tablets (Enteric-coated): 500 mg

• Tablets (Plain): 500 mg

• Suspension (Paediatric): NOT AVAILABLE in India

• Rectal suppositories/enemas: NOT AVAILABLE in India

INDICATIONS + DOSING — FOR CLINICIAN USE ONLY

Primary Indications (Approved / Standard in India)

1. Ulcerative Colitis — Induction of Remission (Mild to Moderate Active Disease)

Parameter Recommendation

Starting dose 500 mg twice daily

Titration Increase by 500 mg every 2–3 days as tolerated

Usual maintenance dose 2–3 g/day in 3–4 divided doses

Maximum dose 4 g/day

Clinical Notes:

• Use enteric-coated formulation to minimise gastric irritation

• Duration for induction: 6–12 weeks typically

• Take with or after food

1. Ulcerative Colitis — Maintenance of Remission

Parameter Recommendation

Starting dose 1 g/day in divided doses

Titration Not typically required

Usual maintenance dose 1–2 g/day in 2–4 divided doses

Maximum dose 2 g/day for maintenance

Clinical Notes:

• Long-term therapy to prevent relapse

• Continue folic acid supplementation (5 mg weekly)

1. Rheumatoid Arthritis

Parameter Recommendation

Starting dose 500 mg once daily

Titration Increase by 500 mg every week as tolerated

Usual maintenance dose 2–3 g/day in 2–3 divided doses

Maximum dose 3 g/day

Clinical Notes:

• Onset of clinical effect: 6–12 weeks; counsel patient regarding delayed response

• Often used in combination with other DMARDs (methotrexate, hydroxychloroquine)

• Enteric-coated formulation preferred

Secondary Indications — Adults Only (Off-label, if any)

Indication Dose Duration Notes

Ankylosing Spondylitis — OFF-LABEL Starting: 500 mg BD; Titration: Increase weekly to 2–3 g/day in divided doses; Max: 3 g/day Long-term; assess response at 8–12 weeks Specialist only; Indian rheumatology practice; evidence from international guidelines

Psoriatic Arthritis — OFF-LABEL 1–3 g/day in divided doses (start low, titrate) Long-term Specialist only; used for peripheral arthritis; EULAR recommendations

Reactive Arthritis — OFF-LABEL 2–3 g/day in divided doses 3–6 months initially Specialist only; Indian rheumatology practice

PAEDIATRIC DOSING (Specialist Only)

Primary Indications

1. Ulcerative Colitis (Paediatric)

Age/Weight Starting Dose Titration Usual Maintenance Maximum

≥6 years 10–15 mg/kg/day in 2 divided doses Increase gradually over 1–2 weeks 40–60 mg/kg/day in 3–4 divided doses 2 g/day (or 60 mg/kg/day, whichever is lower)

Clinical Notes:

• Enteric-coated tablets may need to be crushed if child cannot swallow whole (suspension not available in India)

• Folic acid supplementation recommended

• Monitor CBC, LFTs at baseline and periodically

Secondary Indications — Paediatrics (Off-label, if any)

Indication Dose Duration Notes

Juvenile Idiopathic Arthritis (JIA) — OFF-LABEL Starting: 10–15 mg/kg/day in 2 divided doses; Titration: Increase over 4 weeks to 30–50 mg/kg/day; Max: 2 g/day Long-term; assess response at 8–12 weeks Specialist paediatric rheumatology only; IAP/Indian specialist practice

Age Restriction: Not recommended below 2 years of age except under specialist supervision due to limited safety data and risk of kernicterus in neonates/young infants.

60 No dose adjustment required

30–60 Use with caution; monitor for toxicity; consider dose reduction

<30 Avoid use; if essential, use lowest effective dose under specialist supervision

Haemodialysis Limited data; avoid if possible; not significantly dialysable

• Known hypersensitivity to sulfasalazine, sulfonamides, salicylates, or any excipient

• Acute porphyria

• Intestinal or urinary tract obstruction

• Severe hepatic impairment

• Severe renal impairment (eGFR <30 mL/min)

• Infants <2 years of age (risk of kernicterus)

• Blood dyscrasias (pre-existing severe leucopenia, thrombocytopenia)

• G6PD deficiency (increased risk of haemolysis; monitor closely if essential)

• Slow acetylator phenotype (higher risk of adverse effects)

• History of allergic reactions to any medication

• Asthma (may exacerbate in some patients)

• Blood disorders or history of bone marrow suppression

• Male fertility concerns (reversible oligospermia — counsel patients)

• Concurrent use with other myelosuppressive or hepatotoxic drugs

• Folate deficiency or risk thereof

• Elderly patients (increased sensitivity to adverse effects)

Parameter Details

Risk category Generally considered safe (no evidence of teratogenicity at therapeutic doses)

Preferred alternatives Mesalazine (mesalamine) may be preferred in some cases due to better tolerability

When to use Continue if required for IBD control — flare prevention outweighs theoretical risks; commonly used in Indian practice

Folic acid Mandatory supplementation: 2–5 mg/day (sulfasalazine inhibits folate absorption)

Monitoring Maternal CBC, folate levels; fetal growth monitoring

Parameter Details

Breastfeeding compatibility Compatible with breastfeeding in most cases

Preferred alternatives Mesalazine if concerns arise

Drug levels in milk Low (sulfapyridine metabolite detected in small amounts)

Infant monitoring Observe for bloody diarrhoea, jaundice, rash, poor feeding; extra caution in preterm infants or those with G6PD deficiency

Parameter Recommendation

Starting dose 500 mg once daily (lower end of dosing range)

Titration Slower — increase by 500 mg every 5–7 days as tolerated

Extra risks Increased susceptibility to bone marrow suppression, renal impairment, GI adverse effects

Monitoring More frequent CBC and renal function testing

Drug/Class Interaction Management

Methotrexate Sulfasalazine inhibits folate metabolism; additive toxicity; increased risk of hepatotoxicity and myelosuppression Monitor LFTs, CBC closely; ensure adequate folic acid supplementation

Azathioprine / 6-Mercaptopurine Additive myelosuppression Monitor CBC frequently; consider dose reduction of one or both agents

Digoxin Reduced digoxin absorption Monitor digoxin levels; may need dose adjustment

Warfarin Enhanced anticoagulant effect Monitor INR closely; adjust warfarin dose as needed

Drug/Class Interaction Management

Folic acid antagonists (trimethoprim, pyrimethamine) Additive folate deficiency risk Ensure adequate folic acid supplementation

Oral iron supplements Reduced sulfasalazine absorption Separate administration by at least 2 hours

Antacids / PPIs May affect absorption of enteric-coated tablets Avoid taking together; separate by 2 hours if possible

Hypoglycaemic agents Sulfasalazine may enhance hypoglycaemic effect Monitor blood glucose

• Nausea, vomiting, dyspepsia

• Anorexia

• Headache

• Skin rash, pruritus

• Abdominal discomfort, diarrhoea

• Reversible oligospermia (in males)

• Orange-yellow discolouration of urine

• Staining of soft contact lenses

Adverse Effect Notes

Stevens-Johnson Syndrome / Toxic Epidermal Necrolysis Immediate discontinuation required; hospitalisation needed

Agranulocytosis / Pancytopenia Usually occurs in first 3 months; discontinue immediately; urgent haematology referral

Hepatotoxicity (drug-induced hepatitis) Monitor LFTs; discontinue if significant elevation

Pancreatitis Rare; discontinue if suspected

Pulmonary toxicity (pneumonitis, fibrosis) Rare; discontinue and investigate if respiratory symptoms develop

Haemolytic anaemia Especially in G6PD deficiency; discontinue immediately

Severe hypersensitivity reactions (DRESS syndrome) Discontinue immediately

After initiation / first 3 months CBC and LFTs every 2–4 weeks (highest risk period for blood dyscrasias)

Stable long-term therapy CBC, LFTs, RFTs every 3 months

Clinical monitoring Watch for rash, fever, sore throat (early signs of blood dyscrasia), GI symptoms

Additional Folic acid supplementation status; in males — counsel regarding fertility

• Sazo® (Wallace/Abbott)

• Saaz® (Torrent)

• Salazar® (Sun Pharma)

• Sulfazine® (Cipla)

• Iwasulf® (Intas)

• Multiple generic enteric-coated formulations available

Notes:

• Included in NLEM 2022 (for inflammatory bowel disease and rheumatoid arthritis)

• NPPA ceiling price applicable for scheduled formulations

• Government supply available at subsidised rates

1. Enteric-coated preferred: Always prescribe enteric-coated formulation to reduce upper GI adverse effects (nausea, dyspepsia).

1. Folic acid mandatory: Co-prescribe folic acid (5 mg weekly or 1 mg daily) to prevent folate deficiency and reduce mucosal adverse effects.

1. Delayed onset in RA: Counsel patients that clinical benefit in rheumatoid arthritis takes 6–12 weeks; do not abandon therapy prematurely.

1. Male fertility: Reversible oligospermia occurs in up to 80% of males — counsel before starting; fertility typically recovers 2–3 months after stopping.

1. First 3 months critical: Highest risk for serious haematologic adverse effects (agranulocytosis) is in the initial 3 months — monitor CBC every 2–4 weeks during this period.

1. Cosmetic warning: Drug causes orange-yellow discolouration of urine and may permanently stain soft contact lenses — inform patients.

ulcerative-colitis; rheumatoid-arthritis; DMARD; 5-ASA; sulfonamide; enteric-coated; NLEM-India; pregnancy-compatible; folate-supplementation; oligospermia; Sulfasalazine

RxIndia v1.0 — 12 May 2025

• CDSCO approved product labelling

• Indian Pharmacopoeia / National Formulary of India

• NLEM 2022

• API Textbook of Medicine (11th edition)

• AIIMS Gastroenterology and Rheumatology Protocols

• Indian Rheumatology Association Treatment Guidelines

• IAP Guidelines (Paediatric IBD management)

• Goodman & Gilman's The Pharmacological Basis of Therapeutics (supportive reference)