IM/IV Overdosage of folic acid antagonists 10 mg/m2 given every 6 hr until the MTX serum conc is <10-8 M. IMMegaloblastic anaemia Max: 1 mg daily. May be parenterally by IM/IV inj or IV infusion. Dilute w/ either 1 L of 5% w/v glucose in water for inj or normal saline.
Monitor MTX serum conc to determine the optimal dose & duration of therapy. Prolonged MTX excretion due to renal insufficiency; adequate hydration. May reduce the efficacy of folic acid antagonist. Pregnancy, lactation.