Is Insulin (Lantus, Humalog) Safe for Cats?
Why it’s a problem
Cats prescribed insulin for diabetes are dosed very precisely, and even a small extra amount can crash their blood sugar. A cat that bites into an insulin pen can absorb drug through its mouth, so exposure is not limited to swallowed liquid. Untreated hypoglycemia can progress to seizures, coma, and death within hours.
How to keep your pet safe
Keep pens and vials in the refrigerator behind a closed door, and dispose of used pens and needles in a container pets cannot open. Never change a dose without your vet, and never use another pet’s or a person’s insulin. Ask your vet ahead of time what to do if you miss or double a dose.
Warning signs to watch for
Sudden weakness, staggering, trembling, glassy stare, unusual vocalizing, seizures, collapse, cold paws, coma.
When to call the vet
Contact your vet or a pet poison hotline right away, before symptoms start, since hypoglycemia in a small cat can go from wobbliness to seizures quickly. Follow professional guidance on offering food or syrup — never force liquid into a cat that cannot swallow.
Common questions
My cat chewed my Lantus pen — is that dangerous?
Yes. Insulin can be absorbed through the mouth lining, and overdose causes dangerous low blood sugar. Call your veterinarian or a pet poison hotline immediately, even if the cat seems fine.
I think I double-dosed my diabetic cat — what should I do?
Call your vet or an emergency clinic right away. Double doses can cause hypoglycemia, and your vet may want to monitor blood glucose for hours rather than have you wait at home.
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).