Drug Interaction Report

MONITOR: Parenteral hydration with sodium bicarbonate during treosulfan infusion has been related to an increase of skin disorders like rash and dermatitis. The mechanism of the interaction may be acceleration of the pH-dependent formation of alkylating epoxides. Also, this combination may induce bladder injury from activation of treosulfan in alkaline urine.

MANAGEMENT: Caution is advised when parenteral sodium bicarbonate is used during treosulfan infusion. Patients should be monitored for increased skin disorders such as rash and dermatitis, and for bladder injury. Some experts discourage the alkalinization of patients during treatment with treosulfan and recommend a split-dose or continuous IV infusion regimen of high-dose treosulfan to avoid risk of methanesulfonic acid induced acidosis.