Acetaminophen (Tylenol®, Paracetamol, APAP, N-acetyl-p-aminophenol) is a pain relief and fever-reducing medicine people use for many types of pain. It’s a popular over-the-counter oral medication used alone or in “combination” medications for headaches, pain, colds, flu and menstrual discomfort. It’s often combined with other drugs including aspirin, opioids, antihistamines, decongestants and caffeine.
Acetaminophen comes in tablets, capsules, gel caps, melt away forms, rectal suppositories and liquid forms — all which can be easily digested by curious critters. And because you can find acetaminophen in just about any household with dogs and cats, unfortunately pets are sometimes too easily exposed to accidental poisoning.
Why is Acetaminophen (Tylenol) toxic or poisonous for dogs and cats?
While acetaminophen is generally safe at the recommended dose for humans…
For dogs and cats, acetaminophen (Tylenol) is toxic (poisonous or deadly)!
Relatively small doses (a single pill or even a small piece of a pill) can be toxic or deadly to any animal species (cats, dogs, ferrets, birds, pigs, primates, and many others).
Why? Because the metabolism (mechanisms for breaking down and removing the drug from the body) is often different in animals than it is in humans. For acetaminophen, the altered or abnormal liver metabolism in certain animals puts them at greater risk of harm from acetaminophen exposure.
How much Acetaminophen (Tylenol) is toxic or poisonous for dogs or cats?
- For cats, it has a narrow margin of safety and in general, any dose or even tiny doses are considered poisonous. Abnormal red blood cell damage (methemoglobemia) can occur quickly.
- For dogs, the toxic amount depends on the weight and health of your dog. The larger the dose ingested, the greater the risk. In dogs, liver damage and dry eye can occur. With very high doses, abnormal red blood cell damage (methemoglobemia) can occur.
What should I do if my dog or cat eats Acetaminophen?
If your pet is NOT doing fine, please follow the emergency instructions below.
If your dog or cat is showing any signs of distress, immediately and safely transport your pet to your veterinarian or closest veterinary emergency clinic.
- Scoop up and take any evidence with you such as the pill bottle (even if chewed), the remaining pills and any additional information you may have.
- In addition, it may be helpful to take an old blanket or some towels as poisoned pets may become nauseated and vomit during the car ride. Vomitus should be checked for any evidence of and amount of pill material present before being discarded (If you can’t do this, save the evidence and in most cases your veterinary staff will check this for you).
“If the exposure just occurred and your pet appears to be stable, get life-saving treatment advice immediately by contacting your veterinarian or Pet Poison Helpline, a 24/7 animal poison control, at 800-213-6680.“
Try to stay calm and provide the information requested by your veterinarian or Pet Poison Helpline. This information is critical to providing the best possible care options for your dog or cat and to identify if and how poisonous it is.
To the best of your ability, provide the following information:
- Accurate account of the incident (including when it occurred)
- The amount of medication missing, if you know how many were there before (have someone count pills while you call for assistance)
- If any other ingredients were in the pills (e.g., antihistamine, caffeine, etc.)
- Your pet’s medical history (including what other medication they may be on)
Always consider that any pet with access to medications may have had access to the acetaminophen (Tylenol) pills, so mention all pets that could have been potentially exposed to your veterinarian and Pet Poison Helpline. The earlier your pet is treated, the less expensive and better the chance for a safe and successful outcome.
What are the signs of acetaminophen (Tylenol) poisoning in a dog or cat?
Pets may show no signs initially, or they may exhibit nausea, vomiting, diarrhea, lethargy, depression, blue gums, weakness, rapid or difficulty breathing, collapse, coma, edema (swelling) of the face and paws (especially in cats), transient keratoconjunctivitis sicca (dry eye) in dogs, dark urine and blood and pale, dark or muddy mucous membranes (gums).
If the ingested acetaminophen was combined with other drugs (e.g., caffeine, antihistamines or opioids), your pet may exhibit additional signs including changes in mental status, ataxia (walking as if drunk), hyperactivity, agitation, tremors, seizures, increased or decreased heart rate, changes in blood pressure and body temperature.
How is Acetaminophen (Tylenol) poisoning diagnosed in a dog or cat?
Your veterinarian will likely make a presumptive diagnosis if there’s possible or known exposure to acetaminophen and/or your pet has any of the clinical signs mentioned above.
There’s a test to detect acetaminophen levels in the blood, but often it can only be run at a specialized laboratory or human hospital. In most cases, it takes too long to receive results because treatment must be started promptly for the health and safety of your pet. In some cases, testing may be used to help confirm the initial diagnosis.
Is there an antidote for acetaminophen poisoning?
There’s no specific antidote for acetaminophen toxicosis, but your veterinarian can administer drugs such as n-acetyl-cysteine (NAC) (also known as Mucomyst and Acetadote), antioxidants (Vitamin C), and liver protectants [such as s-adenosyl-methionine (SAMe) and milk thistle] to greatly reduce the risk of liver damage and methemoglobinemia (if given soon after the exposure). Seek veterinary attention immediately if you think your dog or cat has been poisoned by acetaminophen, as NAC must be started as soon as possible to prevent poisoning.
How is acetaminophen poisoning treated in dogs and cats?
Your veterinarian will provide treatment that’s tailored to the patient’s condition when he/she arrives at the clinic. In general, treatment consists of:
- baseline blood work and frequent monitoring of liver values,
- liver protectants (NAC, SAMe, Marin), and
- intravenous (IV) fluids.
In severely affected patients, additional therapy may be necessary, including oxygen therapy, blood transfusions, monitoring the body’s ability to clot, and additional symptomatic and supportive care.
What’s the prognosis for a dog or cat’s recovery if exposed to acetaminophen?
In general, the sooner you get treatment (and the more aggressive it is), the better the prognosis or chance of recovery for your pet.
It can depend on many factors including the initial health of your pet, the amount of acetaminophen ingested, whether any other drugs were combined with the acetaminophen, how soon decontamination was performed and whether the pet showed any signs of liver damage, coagulopathy (bleeding disorder), methemoglobinemia or anemia at the time treatment was initiated.
Can I prevent my dog or cat from swallowing acetaminophen (Tylenol)?
Yes, here are some tips to pet-proof your home and help keep them safe.
- Never give any human medication to your pet without first consulting your veterinarian.
- Keep all medications out of the reach of your pet.
- Never leave medications unattended when your pet is around. Keep in mind that pets will knock items off counters (cats often knock items off counters only to have the dogs ingest them off the floor!).
Pets will sometimes open lower cabinets, chew through pill bottles, and never even stop if the pills aren’t the tastiest (their sense of taste and smell is different from ours).
- If you drop a pill and can’t find it, first confine your pet to another area of the home and then continue your search for the missing medication. Pets are quick and will often grab it before you can find it. In many cases, even one dropped pill may pose a significant risk for your pet.
- Pets are curious and often love to check out items in the home including purses, backpacks, lunch boxes and suitcases. Remind children and visitors to keep all medications including vitamins and supplements out of your pets reach.
- Always remember to keep your pet happy and healthy by minimizing potential risks in the home environment.
“With any poisoning, get help immediately! It’s less dangerous to your pet, and less expensive for you to treat early!”
*Pet Poison Helpline, is an animal poison control service available 24 hours, 7 days a week for pet owners and veterinary professionals who require assistance treating a potentially poisoned pet! Pet Poison Helpline is available in North America by calling 800-213-6680. Additional information can be found online at www.petpoisonhelpline.com. Pet Poison Helpline is not directly affiliated with LifeLearn.
Dr. Colleen M. Almgren, DVM, PhD, Pet Poison Helpline.
© Copyright 2014 LifeLearn Inc. Used and/or modified with permission under license.