Formulations → Injectable: 50 mg/mL solution; oral solution (syrup): 10 mg/mL in 60 mL; tablets: 12.5, 50 mg
For pulmonary edema & ascites associated with congestive heart failure (CHF)1
Dose (dogs) → Injection: Start with 2 mg/kg q6-8h IV or IM; increase dose in increments of 1 mg/kg to effect (maximum, 5.5 mg/kg q6-8h); oral: up to 6 mg/kg PO q8h
Dose (cats) → Injection: Start with 0.5 mg/kg IV or IM q12h; increase dose in increments of 2.2 mg/kg to effect (maximum, 5 mg/kg q12-24h)
Maintenance dose → Oral: Start with 1 mg/kg PO every 2-3 days up to 2 mg/kg PO q8-12h, depending on response
Key Points
- Conservative doses should be implemented initially, then adjusted to the minimum effective dose based on a target respiration rate.1
- Ideal respiration rate varies based on the individual patient and environmental conditions and is achieved when the patient exhibits a steady, relaxed respiration pattern after stabilization.
- Parenteral furosemide is usually only used for a short period in patients with acute fluid accumulation.
- Single intravenous, subcutaneous, and oral administration may be equally effective to increase urine production in dogs.2
- Also see General Comments.
For fluid retention associated with glomerular disease3
Dose (dogs only) → 1 mg/kg IV or IM q6-12h, with incremental increases of 0.5-1 mg/kg IV or IM q6-12h
Key Points
- Use of diuretics for glomerular disease is reserved for patients with severe pulmonary edema or ascites that interferes with major organ function.3
- Mild peripheral edema is best left untreated in these patients.
- In patients with hypoalbuminemia, further ECF reduction with diuretics can cause severe hypovolemia and circulatory collapse.3
- Parenteral furosemide is usually used for a short period in patients with acute fluid accumulation.3
- Also see General Comments.
For acute management of moderate-to-severe or rapidly progressing hypercalcemia4
Dose (dogs only) → 2-4 mg/kg IV, SC, or PO q8-12h
Key Points
- Furosemide is a temporary supportive treatment for short-term control of hypercalcemia until the primary cause can be identified and corrected.4
- Full hydration should be maintained in patients being treated with furosemide for hypercalcemia.5
- Furosemide is usually reserved for patients that fail to respond to solute diuresis.
- Also see General Comments.
For prevention of cyclophosphamide-induced hemorrhagic cystitis5
Dose (dogs only) → 0.5-2.2 mg/kg PO or IV q24h
- Shown to be effective in reducing the incidence of sterile hemorrhagic cystitis in dogs currently receiving metronomic low-dose oral cyclophosphamide6
General Comments (Furosemide)
- Doses should be adjusted based on individual patient response.
- Renal function and electrolytes, especially potassium, should be monitored to prevent prerenal azotemia.
- In cats: Ototoxicity and hearing loss can occur at high doses.
- Furosemide can potentiate the hypotensive effects of angiotensin-converting enzyme (ACE) inhibitors.
- Severe hypokalemia and hyponatremia can develop during treatment, particularly in patients with reduced food and water intake.
- In cats: Extreme dehydration and hypokalemia can occur when diuretics are administered long-term; careful monitoring is required.