colchicine + verapamil

colchicine + verapamil is a combination of the small molecule drugs colchicine and verapamil. This is not a marketed combination product but refers to the concurrent use of both agents. Colchicine is an anti-inflammatory agent that disrupts microtubule polymerization, used primarily for the treatment of gout and pericarditis. Verapamil is a calcium channel blocker that inhibits L-type calcium channels, used primarily for hypertension, angina, and arrhythmias. Significant pharmacokinetic interaction exists between the two: verapamil inhibits both CYP3A4 and P-glycoprotein (P-gp), leading to increased colchicine exposure and risk of serious toxicity, particularly myopathy and neuromyopathy. Dose reduction or avoidance of the combination is recommended due to the high risk of adverse effects[1][2][3][4][5][6].