Common Drugs Dangerous to Pets

Acetaminophen can be Toxic for your Pets!

Many pet owners assume dogs and cats are just small humans and give them medications and foods commonly used for people.  Keep in mind each species has very specific requirements for medications and drug doses.  For example Acetaminophen (or paracetamol) is one of the most popular pain medications for people, but can be toxic to your dog and is deadly to your cat.

Why Acetaminophen (Tylenol ) can be toxic to your pet? 

In the human body acetaminophen is mostly converted to inactive compounds and it is eliminated from the body by 50 – 60%.  In dogs the elimination process is approximately the same, however less than 3% of acetaminophen is eliminated in cats. High doses can cause acute liver damage and damage to the red blood cells leading to inability to carry oxygen.

In dog’s acetaminophen can be used for pain control at very low doses, however it is almost never used in practice by veterinarians.  Clinical signs of toxicity are not typically observed in dogs unless the dose exceeds 100mg/kg at which time liver damage develops.  Doses of 200mg/kg can result in red blood cell damage and death.  Acetaminophen should never be used in cats.  A dose as low as 10mg/kg will produce poisoning.

Clinical Signs

Clinical signs of toxicity include depression, weakness, rapid respiration, difficulties breathing, purple to blue color of the skin, gums and tongue, jaundice, vomiting, hypothermia, swelling of the face or paws, black blood, and even death.

If your Pet has taken Acetaminophen

If your pet has accidentally ingested some of your acetaminophen, please contact a veterinarian immediately.  Before you call, try to have the strength and amount of medication available including the time it was taken.  The vet will also need to know your pet’s body weight.


The treatment for acetaminophen poisoning is not possible at home.  Your pet will be placed on intravenous fluids and his/her bloodwork will be checked.  Vomiting may be induced, and activated charcoal may be given if the medication was taken within 2-4 hours.  If the bloodwork shows red blood cell damage, a blood transfusion may be required. Oxygen and specific medications will be administered.


The prognosis for recovery in dogs is usually favorable, depending on the dosage. However the prognosis for recovery in cats is questionable, especially if the clinical signs have developed.

Why is your cat so susceptible to acetaminophen? The activity of the enzyme glucuronyl transferase is required in order to be able to eliminate the acetaminophen from the body, and this activity is very low in cats.


Always consult a veterinarian if you are considering giving Tylenol to your dog and you should never give this medication to a cat.   Keep your medications locked away and inaccessible to your pets, as they may eat them if they find them.

If your pet is in pain, your veterinarian will recommend a variety of other pain medications which are safe and work much better for cats and dogs.

Written By: Gala Musters, DVM