40 mg furosemide = 20 mg torsemide = 1 mg bumetanide = 50 mg Fluid overload: Typically 40 mg IV or normal PO dosage IV. Learn about Lasix (Furosemide) may treat, uses, dosage, side effects, drug Oral LASIX may be used in adults for the treatment of hypertension alone or in . In isolated cases, intravenous administration of LASIX within 24 hours of taking. Detailed Furosemide dosage information for adults and children. Initial dose: 20 to 40 mg IV (slowly over 1 to 2 minutes) or IM once; may repeat Oral: Initial dose: 20 to 80 mg orally once; may repeat with the same dose or.