Captopril
Medication Facts
- Performance enhancing
- No, Avoid Drug Combinations
- Total hours to clear
- Not recorded
- Frequently used
- N/A
- ESC ID
- CAPTOP-0171
- Trade names
- Capolen
- Drug type
- ACE inhibitor
- Plasma half-life · hours
- Not Published
- Equine dosing
- 1 mg/kg PO q12h
- Cmax · peak plasma concentration
- 1 ng/mL
- Tmax · time to peak plasma concentration
- 2
- ESC concentration guidance
- May not exceed (LDL) Lowest Detectable Level of .05 ng/mL or 50 picograms per mL
- Primary withdrawal · hours
- 48
- Washout withdrawal · hours
- 0
- ESC control type
- A1 - Generally Controlled - Therapeutic
- Medication report required
- Generally not required, however understand exceptions.
Uses & side effects
Product-specific side effects await source review.
Drug interactions
ACE inhibitors for horses—primarily Benazepril, Quinapril, and Ramipril—carry significant risks when combined with other common equine medications due to their impact on blood pressure and kidney function.1. Critical & High-Risk InteractionsNSAIDs (e.g., Bute, Banamine, Naproxen): Concurrent use is a major concern. NSAIDs can reduce the effectiveness of ACE inhibitors and drastically increase the risk of Acute Kidney Injury (AKI) by further restricting renal blood flow.Diuretics (e.g., Furosemide/Salix): While often used together for heart failure, high doses of diuretics combined with ACE inhibitors can lead to severe hypotension (low blood pressure) and kidney failure.Potassium Supplements or Potassium-Sparing Diuretics (e.g., Spironolactone): ACE inhibitors naturally cause the body to retain potassium. Adding supplements or certain diuretics can lead to hyperkalemia (dangerously high potassium levels), which can trigger cardiac arrhythmias.2. Other Notable InteractionsOther Vasodilators (e.g., Amlodipine, Hydralazine): Using multiple vasodilators simultaneously creates an additive effect that may cause a dangerous drop in blood pressure, leading to weakness or collapse.Insulin: ACE inhibitors may increase sensitivity to insulin, potentially leading to hypoglycemia (low blood sugar).Anesthetics: General anesthesia can cause blood pressure to drop significantly in horses already on ACE inhibitors. Veterinarians often recommend monitoring or temporary cessation before surgery.Corticosteroids (e.g., Dexamethasone): These may decrease the blood-pressure-lowering effects of ACE inhibitors.