Iguratimod

Iguratimod is a conventional synthetic disease-modifying antirheumatic drug (csDMARD) used in the treatment of rheumatoid arthritis. It acts on both T and B lymphocytes to suppress immune response, inhibits production of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-17) to reduce inflammation, and promotes bone formation while inhibiting osteoclast activity for osteoprotective effects.

• Rheumatoid arthritis (RA)
• Sjögren's syndrome
• Ankylosing spondylitis
• Systemic lupus erythematosus (SLE)

Adult Dose (Oral):

• Rheumatoid Arthritis: 25 mg twice daily (morning and evening) after meals
• Some cases: Start with 25 mg once daily for 1-2 weeks to improve tolerance, then increase to twice daily
• Mild renal/hepatic impairment: Dose adjustment usually not required (caution needed)
• Often used alone or in combination with methotrexate or other DMARDs

Child Dose: Safety and efficacy not established

Common Side Effects:

• Nausea
• Stomach pain
• Diarrhea
• Indigestion
• Headache
• Dizziness
• Tiredness
• Mild increase in liver enzymes (ALT, AST)
• Mild decrease in blood counts

Precautions:

• Liver toxicity: May cause elevated liver enzymes (ALT, AST); regular LFTs required (baseline, then periodically); stop if significant hepatotoxicity occurs
• Bone marrow suppression: Can cause leukopenia, neutropenia, anemia, or thrombocytopenia; monitor CBC regularly
• Renal impairment: Use with caution; monitor renal function
• Infections: Immunomodulator may increase risk of infections; avoid use in active infections
• Gastrointestinal effects: Take after meals to reduce GI upset

Contraindications:

• Hypersensitivity to Iguratimod or formulation components
• Severe hepatic impairment
• Pregnancy
• Breastfeeding

Drug Interactions:

• Caution with other immunosuppressants, DMARDs, hepatotoxic drugs, or anticoagulants
• Combination with methotrexate is common but needs close monitoring

Use in Pregnancy: Contraindicated; teratogenic risk and not enough safety data; effective contraception required during treatment and for some time after discontinuation.

Use in Lactation: Contraindicated; not enough safety data.

Renal Impairment: No dose adjustment usually required in mild renal impairment (caution needed); monitor renal function.

Hepatic Impairment: No dose adjustment usually required in mild hepatic impairment (caution needed); monitor LFTs regularly; contraindicated in severe hepatic impairment.