Also sold as Zestril, Prinivil, Zestoretic (with a diuretic)
The human product is the problem: the strength, the coating, or an added ingredient makes it wrong for a dog even when the active ingredient is familiar.
Lisinopril is a human ACE inhibitor. Dogs with heart disease are usually given enalapril or benazepril instead, so a dog that swallows lisinopril is getting a drug chosen for a different species. Blood pressure falling is the concern.
Source-backed guidance. Not individualized veterinary advice.(more)
Compiled from veterinary poison-control and medical references, including the ASPCA Animal Poison Control Center, Pet Poison Helpline, and Merck Veterinary Manual.
Part of Heart and blood-pressure medication on our medication safety hub.
Do not wait for symptoms and do not wait until you have filled in the form below. Call first, then use the checklist while you are on the phone.
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Exposure details to have ready
These are the questions a veterinarian or poison-control operator will ask. Fill in what you know and leave the rest blank. This tool does not estimate a dose or a risk score: medication risk depends on the exact ingredient, strength, and formulation, so the assessment has to come from the clinician on the call.
- Keep the package, blister pack, or prescription bottle. The strength and the full ingredient list are what make the advice specific.
- Do not induce vomiting unless a veterinarian or poison-control professional tells you to. It is the wrong move for several medications and can cause harm on its own.
- Do not give milk, food, salt, hydrogen peroxide, or any home remedy on your own.
- Do not give a second dose of anything to make up for one you think was missed.
- Count what is left in the packet, so the number missing can be worked out.
Your exposure summary
Read this down the phone or paste it into a message to your vet. It stays on your device; nothing here is sent to DogSafe.
Why Lisinopril (Zestril) needs caution
Lisinopril relaxes blood vessels by blocking angiotensin-converting enzyme. Vets treat canine heart disease with drugs from the same family, but generally enalapril or benazepril rather than this one. After an accidental exposure the effects to watch for are low blood pressure showing as weakness, wobbliness or collapse, along with effects on the kidneys and on potassium. A dog with existing kidney or heart disease, or one already on a diuretic, has the least margin. Combination products add a diuretic and change the picture.
Part of the Amlodipine (Norvasc) guide
For related dog-safety questions and product-by-product answers, see the complete amlodipine (norvasc) guide.
Signs to watch for
Vomiting, diarrhea, weakness, wobbliness, a racing or unusually slow heart, or collapse
Related items
Check the exact item or ingredient before assuming two similar exposures carry the same risk.
What to do next
Keep the box or blister pack, count what is missing, note the strength and the time, and say on the call that this was a human product.
🚨Step-by-step: what to do in the first 10 minutes →Available 24/7. A consultation fee may apply.
A closer look at lisinopril (zestril)
Lisinopril relaxes blood vessels by blocking angiotensin-converting enzyme. Vets treat canine heart disease with drugs from the same family, but generally enalapril or benazepril rather than this one. After an accidental exposure the effects to watch for are low blood pressure showing as weakness, wobbliness or collapse, along with effects on the kidneys and on potassium. A dog with existing kidney or heart disease, or one already on a diuretic, has the least margin. Combination products add a diuretic and change the picture. The details below use the specific facts for this exposure, rather than treating it like every other medication question.
1. Start with the exact exposure
For a closely related comparison, read Amlodipine (Norvasc). A human tablet is not a scaled-down dog dose. The strengths are chosen for a human body, and coatings, combination ingredients, and extended-release designs make the human product behave differently again.
2. Use the facts to decide whether to monitor or call
Another helpful reference is Metoprolol (Lopressor). Prevent further access and keep the packaging. Do not attempt to work out a dog-sized fraction of a human dose, and do not induce vomiting unless directed. Call for any uncertain amount, for a combination or extended-release product, for a dog that already has heart or kidney disease, and for any sign at all.
3. If the details are uncertain
Follow the first 10 minutes guide. Keep the box or blister pack, count what is missing, note the strength and the time, and say on the call that this was a human product.
FAQ
A human tablet is not a scaled-down dog dose. The strengths are chosen for a human body, and coatings, combination ingredients, and extended-release designs make the human product behave differently again.
Prevent further access and keep the packaging. Do not attempt to work out a dog-sized fraction of a human dose, and do not induce vomiting unless directed.
Call for any uncertain amount, for a combination or extended-release product, for a dog that already has heart or kidney disease, and for any sign at all.
- Merck Veterinary Manual — poisonings from human prescription drugs (cardiovascular agents)
- ASPCA Animal Poison Control Center — human medications
- Pet Poison Helpline — top 10 human medications poisonous to pets
- Merck Veterinary Manual: Poisonings from human prescription drugs
- ASPCA Animal Poison Control
- Pet Poison Helpline: Top 10 human medications poisonous to pets