Use of SSZ in Rheumatoid Arthritis
SSZ (Azulfidine) is often used in early and mild disease. Its potential for toxicity is low; it is often combined with other DMARDs. SSZ was designed as a two-component drug including sulfapyridine, which is antimicrobial, and 5-aminosalicylic acid (5-ASA), which is antiinflammatory.
Dosage: 1 to 3 g/day in divided doses. To reduce gastrointestinal (GI) toxicity, start at 500 mg/day and increase by 500 mg each week.
- • Nausea and vomiting: less likely to occur with slow dose titration, the use of enteric coated tablets, and if taken with meals.
- • Rash: occurs in approximately 1% to 5%, usually within first 3 months.
- • Headache and dizziness.
- • Azoospermia: reversible within 3 months upon cessation of therapy.
- • Agranulocytosis: occurs in <3% of patients and usually within the first 3 months of therapy. Prescribers should be vigilant in monitoring for this potentially fatal toxicity.
- • Hemolysis: can occur if the patient has G6PD deficiency.
- • Pulmonary infiltrates with eosinophilia.
- • Hypersensitivity reactions: can include hepatic enzyme elevation ± fever, adenopathy, and rash. The drug should be discontinued.
Monitoring: complete blood count (CBC), creatinine, and liver transaminases every 2 to 4 weeks for the first 3 months, then every 8 to 12 weeks for the next 3 to 6 months, then every 12 weeks.
Precautions: dose should be decreased by 50% if creatinine clearance (CrCl) <50 mL/minute with close monitoring.