Acetaminophen (Tylenol) is one of the most dangerous substances known to cats. A single regular-strength tablet (325mg) can kill a cat. Cats completely lack the enzyme needed to metabolise it, causing methemoglobinemia (inability to carry oxygen) and simultaneous liver necrosis. Any exposure is an emergency.
🚨 Emergency
This substance is toxic to cats. If your cat has already ingested it, call ASPCA Poison Control at (888) 426-4435 immediately.
Toxic Dose Information
This table shows toxic thresholds — not recommended doses. There is no safe dose.
| Dose / Amount | Effect | Risk |
|---|---|---|
| Any dose | FATAL RISK | Immediate emergency |
| 10mg/kg | Early toxicity | Methemoglobin forming |
| 50mg/kg | Severe — often fatal | Multi-organ failure |
| Single 325mg tablet | Lethal for most cats | Critical emergency |
ℹ️ Note: There is NO safe dose of acetaminophen for cats. This is one of the very few substances where even partial exposure (licking a dissolved tablet, nibbling a coated pill) can cause fatal toxicity.
Never Use These Products
- Tylenol or any acetaminophen product
- Cold & flu medications (nearly all contain acetaminophen)
- 'PM' sleep formulations
- Combination pain relievers with 'APAP'
- Any amount under any circumstances
Signs of Toxicity
- None — never use acetaminophen in cats under any circumstances
Signs of Toxicity
🚨 Emergency Steps
Any ingestion of can cats have tylenol warrants an immediate call to Poison Control.
Frequently Asked Questions
Cats lack glucuronyl transferase, the liver enzyme that metabolises acetaminophen in humans and dogs. It converts to NAPQI which destroys red blood cells' oxygen-carrying capacity.
If they licked or chewed it, call Poison Control immediately. Sniffing without ingestion is likely safe, but any licking warrants a call.
Brown or chocolate-coloured gums appearing within 1–4 hours is the most distinctive sign. Lethargy, vomiting, and laboured breathing also appear rapidly.
N-acetylcysteine (NAC) can be given within hours of exposure to reduce liver damage. It must be administered by a vet — every minute counts.
With very fast treatment (within 2–4 hours), survival is possible. Without treatment, or with delayed treatment, it is often fatal.