Major
Colchicine × Fluconazole
Antigout agents×Antifungals, triazole derivatives
Mechanism
Fluconazole at 200 mg/day or above blocks CYP3A4 – the main colchicine clearance route. Colchicine plasma levels rise; myopathy risk grows with prolonged therapy.
Symptoms
Profuse diarrhoea, vomiting, abdominal pain. With prolonged combination: muscle weakness, peripheral neuropathy, falling leukocytes and platelets.
Management
For short fluconazole courses (up to 7 days), no special measures are needed. For prolonged systemic therapy with preserved renal function, colchicine 0.3 mg every other day. In chronic kidney disease, do not prescribe; alternative for gout: intra-articular glucocorticoid.