Indications to reduce the intravenous dose of colchicine:
(1) decreased renal function ( creatinine clearance 10 - 50 mL per minute)
(2) advanced age (limit not defined; will use >= 65 years)
(3) concomittant therapy with inhibitors of CYP3A4 (diltiazem, grapefruit juice, ketoconazole, erythromycin, toleandomycin, etc) specifically or generalized inhibition of P450 (cimetidine)
Contraindications to intravenous therapy:
(1) poor renal function, with creatinine clearance < 10 mL per minute
(2) extrahepatic biliary obstruction
(3) combined renal and hepatic disease
(4) serious allergic reaction
Additional recommendations:
(1) Double check all calculations used to determine dose and calculation.
(2) Observe recommended limits for colchicine (Wallace and Singer, 1988)
(2a) maximum IV dose: 2-3 mg without dosage reductions
(2b) maximum cumulative dose: 4 mg without dosage reduction
(2c) avoidance of any additional colchicine for 7 days
(3) Closely monitor the patient for signs of toxicity.
