Rheumatoid Arthritis: Initiating a DMARD

Patient B-217 is a 50-year-old woman with a 3-month history of pain, swelling and morning stiffness in both hands and wrists. She has difficulty gripping and opening jars. On examination there is bilateral synovitis of the metacarpophalangeal and proximal interphalangeal joints, with reduced grip strength. Blood tests: ESR 46 mm/h, CRP 28 mg/L, rheumatoid factor positive, anti-CCP antibodies strongly positive. X-rays of the hands show periarticular osteopenia and joint space narrowing in the MCP joints. She has no other significant medical history. Current medications: trimethoprim 200 mg twice daily for recurrent cystitis, and ibuprofen 400 mg three times daily as required for pain. She is a non-smoker and drinks 4 units of alcohol per week. Blood pressure 128/78 mmHg, pulse 72 bpm. Weight 70 kg. Renal function: serum creatinine 1.0 mg/dL, eGFR 75 mL/min/1.73m2. Liver function tests, including AST and ALT, are normal. She is not pregnant and has no known drug allergies. The rheumatology team asks you to write a prescription for a disease-modifying antirheumatic drug and any co-prescription required as part of standard therapy. Consider the dosing schedule, monitoring requirements, and any drug interactions.