Is Lisinopril (Zestril) Safe for Cats?
Why it’s a problem
Cats are small enough that even a single human tablet can overshoot a tolerable exposure. ACE inhibitor toxicity in cats has been reported to cause low blood pressure, weakness, elevated potassium, and kidney injury. Cats with existing kidney disease are especially vulnerable.
How to keep your pet safe
Store lisinopril in closed cabinets, and remember that cats knock bottles off counters — keep pills in containers that close securely. Blood-pressure treatment for a cat must come from a veterinarian.
Warning signs to watch for
Profound lethargy, weakness, wobbliness, vomiting, pale gums; larger exposures: collapse, little or no urine, irregular heartbeat from high potassium.
When to call the vet
Call your veterinarian or a pet poison hotline promptly after any exposure — cats may need bloodwork to check potassium and kidney values. Report the tablet strength and your cat’s weight.
Common questions
My cat swallowed one of my blood-pressure tablets — is it dangerous?
Yes — a single human tablet is a significant dose for a cat and can affect blood pressure and kidneys. Call your vet or a pet poison hotline right away.
Can cats take ACE inhibitors?
Only when a veterinarian prescribes them for specific heart or kidney conditions. Never share your own blood-pressure medication with a cat.
More medications hazards for cats
This page is general educational information, not a substitute for professional veterinary advice. Every pet is different — if your animal ate or touched something concerning, contact your veterinarian or a pet poison hotline right away. In the US: Pet Poison Helpline (855) 764-7661, ASPCA Animal Poison Control (888) 426-4435 (fees may apply).