Suspect poisoning? US: ASPCA Poison Control (888) 426-4435 · UK: 01202 509 000 · Severe symptoms → nearest emergency vet now.

My dog chewed a raw insulin pen that was left on the counter — is this more dangerous than an accidental injection?

Dogs · Emergency guide

Last reviewed: 2026-09-05 · Reference ranges: ASPCA, Pet Poison Helpline & Merck Veterinary Manual

Short answer

Yes, a chewed insulin pen is an urgent emergency. Whether the insulin is injected or swallowed, it will be absorbed and cause a severe drop in blood sugar, potentially within 30 minutes. A chewed pen means the entire cartridge's dose could be ingested at once, which is extremely dangerous. Bring the pen to the vet immediately, and if your dog is awake and able to swallow, offer a small amount of honey or syrup on the way. Call your vet or the ASPCA Poison Control line at 888-426-4435 right away for specific guidance.

Why is this dangerous?

Insulin injected or chewed from a pen, and oral drugs such as metformin and glipizide, all lower blood glucose. A pet that has taken too much becomes hypoglycaemic — the brain runs out of fuel within 30 minutes to a few hours.

Pets already on insulin are at extra risk: a double dose or a chewed insulin pen is a common household accident.

Why speed matters

Delaying care significantly worsens outcomes. Some signs appear hours or days later, so "looks fine right now" is not a reason to wait.

Signs to watch for

  • Weakness, wobbliness, staggering
  • Confusion, staring, unusual behaviour
  • Tremors, seizures
  • Collapse, coma
  • Vomiting and drooling before neurological signs

What to do right now

  1. If the pet is awake and able to swallow, offer a small amount of honey, syrup or food and call the vet at once.
  2. Do not put anything in the mouth of a drowsy or seizing pet — it can be inhaled.
  3. Go to the vet; blood glucose needs to be measured and monitored for hours.
  4. Bring the pen or bottle so the dose taken can be estimated.
If your pet shows any of the signs above, go to the nearest emergency vet now and call ahead.

The step-by-step response, from the first minute to the vet visit, is in our Diabetes Medicines (Metformin, Insulin) emergency guide.

Open the full emergency guide: Diabetes Medicines (Metformin, Insulin) →