Furosemide

Cats with pulmonary oedema (stage C) must be treated with a loop diuretic – either furosemide or torsemide (torasemide). The route of administration and dosage depends on the nature and severity of clinical signs at presentation, radiographic changes, and response to initial therapy. Cats presented for veterinary attention due to dyspnea and severe tachypnea (most will have an RR in the 70s or 80s) typically have severe pulmonary oedema, and so need to be treated with high-dose parenteral furosemide. The initial dose for such severe cases is 3-6 mg/kg, preferably IV, but IM can be used if catheter placement is too stressful. A constant rate infusion of 0.5-1 mg/kg/h can also be administered.