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I just saw my cat swallow a 500 mg metformin pill I dropped — what are the very first things I must do in the next 10 minutes?

Cats · Emergency guide

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

Short answer

Your first step is to call your vet or an emergency clinic immediately — do not wait. While you're on the phone, locate the pill bottle so you can tell them the exact strength and how many are missing. If your cat is still awake and acting normally, you can offer a small spoonful of honey or corn syrup to help raise her blood sugar while you prepare to leave. Do not attempt to induce vomiting unless your vet explicitly instructs you to. Grab your cat carrier, the pill bottle, and head to the vet; her blood glucose will need to be monitored for several hours to prevent a dangerous crash.

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) →