What is acetaminophen toxicosis?
Acetaminophen, also known as paracetamol or Tylenol, is one of the most common analgesics on the market. It’s available over-the-counter to treat mild pain and fever in humans and is found in many homes. Acetaminophen comes in several forms, including pills (tablets and gel caps) and liquid. It may even be one of several ingredients in a combination product, such as cold and flu medication. Due to its familiarity and common use in humans, pet owners sometimes mistakenly believe that this drug will provide the same relief to their pets. However, in dogs and cats, the ingestion of drugs like Tylenol can result in toxicosis, the veterinary medical term for poisoning. Acetaminophen toxicosis in your pet can cause serious health complications and even death.
Acetaminophen toxicosis in pets can be quite serious and unfortunately, it is also a common occurrence. In 2024, over-the-counter (OTC) medications like acetaminophen ranked first in the ASPCA Animal Poison Control Center’s list of frequent pet toxins. Acetaminophen toxicity is widespread. Pet Poison Helpline maintains a list of the most commonly reported pet toxins by state. Here in Washington where our hospital is located, it has not left the top 20 since 2019. The team at Animal Emergency Care wants you to be aware of the risks and signs of acetaminophen poisoning (or acetaminophen toxicosis) in your pet, what to do if you suspect your pet has ingested Tylenol or another drug containing acetaminophen, and ways you can help protect your pet from accidentally eating something toxic.
What happens to a pet with acetaminophen toxicosis?
When a pet ingests a toxic amount of acetaminophen many changes occur in the body.
Acetaminophen primarily adversely affects pets through damage to the liver (hepatotoxicosis) and the red blood cells (methemoglobinemia). Dogs are more likely to suffer liver damage, and cats are more prone to red blood cell damage, but both species are at risk for both side effects if they have ingested acetaminophen.
While experiencing toxicosis, your pet’s hemoglobins–the red blood cells that carry oxygen throughout the body–become methemoglobins, an altered form of hemoglobin which cannot deliver oxygen. Without oxygen, the body’s systems weaken and may eventually cease to function.
It is vital that treatment for acetaminophen poisoning begin as soon as possible. Liver and red blood cell damage can begin as quickly as thirty minutes after ingestion. Peak plasma concentrations are usually reached within one hour. Prompt medical treatment is especially important for cats, who are at a higher risk of fatality from acetaminophen toxicosis due to low levels of an enzyme called glucuronyl transferase which the liver requires to process acetaminophen.
Signs of acetaminophen toxicosis in your pet
Clinical signs of acetaminophen poisoning commonly include:
- Vomiting
- Lethargy
- Lack of appetite
- Weakness
- Listlessness
- Hypothermia
- Swollen face or paws
- Discolored gums
- Difficulty breathing
Even small amounts of acetaminophen may place your pet at risk of serious health complications. Both dogs and cats present similar symptoms, however dogs are more likely to exhibit clinical signs when the dose they have ingested is higher than 100 mg per kilogram, or after repeated exposure to lower doses.
For example: A bottle of “regular strength” Tylenol contains one hundred tablets at 325 mg each, so a dog who weighs 40 lbs may only need to ingest 5.5 pills to reach toxicosis. A cat can develop symptoms after ingesting as little as 10 mg per kilogram. This means a 7 lb cat may only need to ingest 1/10 of a pill to reach toxicosis.
Acetaminophen toxicosis diagnosis and treatment
Your pet’s prognosis–the likely outcome of an illness–depends on how much acetaminophen they have eaten, as well as the length of time between ingestion and treatment. Be sure to share any information you have with your veterinary team, including how many pills you suspect (or know) your pet ingested, the dosage per pill in milligrams, and whether it was “fast-release.” If the medication bottle is available, it may be helpful to have it nearby when calling your veterinarian or poison control service or to bring it with you if you head to the emergency veterinary hospital.
The treatment plan for a cat or dog with acetaminophen toxicosis varies depending on how much of the drug they ingested, how long ago, and other factors related to an animal’s unique health and medical history. Some common diagnostic and treatment options for acetaminophen poisoning include but are not limited to:
- Induced vomiting
- Activated charcoal with a cathartic
- Intravenous fluids (IV fluids)
- Anti-nausea medication (antiemetics)
- N-acetylcysteine, an amino acid that can reduce the extent of the red blood cell damage
- Ascorbic acid or methylene blue
- Liver enzyme tests
When analgesic ingestion is caught early, the prognosis is generally positive and the cost of care is typically lower.
How to pay for emergency vet care when your pet eats acetaminophen
Pet Insurance
Some families choose to pay for pet insurance coverage or their dog or cat to help afford the cost of treatment in the event of unexpected illness or injury. Some pet insurance plans, like Trupanion, can work directly with your veterinarian to pay for care and do not rely on reimbursement models where you pay the veterinarian and are later reimbursed by the insurance company. However, pet insurance is only helpful in an emergency if your dog or cat is already insured, as coverage cannot be applied retroactively.
Pet Savings Account
Other pet owners keep a pet health savings account. A pet health savings account allows you to save for emergencies and, if there are no accidental poisonings or other veterinary expenses, you still have the fund at your disposal.
Financing Options and Payment Plans for Veterinary Care
Emergencies are never planned and many pet owners need to strategize to cover unexpected veterinary expenses to ensure your dog or cat can receive treatment for acetaminophen toxicosis right away. If you don’t have a pet insurance plan or savings set aside, there are several other options for covering the costs of emergency care and hospitalization.
Your veterinarian may accept payment options such as Cherry, All Pet Card, Scratch Pay, or CareCredit, which pay for care upfront and allow qualifying pet owners to pay smaller installments on their balance over a longer period of time, sometimes with a window for deferred interest. Animal Emergency Care understands credit-based financing is not an option for some households and also offers payment plans which do not require a credit check to qualifying clients. It is always worth asking your veterinary team to tell you which financial resources may be available at their practice to help make treatment more financially accessible for your household. Visit the paying for care page to learn more about the many payment methods accepted at Animal Emergency Care or call our hospital to speak with a team member directly about your situation. We’re here to help!
How to prevent acetaminophen toxicosis in pets
Fortunately, there are several ways to reduce the risk of your cat or dog experiencing acetaminophen poisoning.
Only give medication under the guidance of a veterinarian
Unfortunately, most cases of acetaminophen toxicosis are owner-administered. This means they are caused by a well-meaning pet owner who didn’t understand that the over-the-counter pain reliever that they thought could help would actually make their pet dangerously ill. Always contact your veterinarian if your pet appears to be in pain and before giving them any medication that they have not been prescribed. A veterinarian has the knowledge and experience to ensure your pet has the best chance of recovering from their illness or injury. If you need an answer when your own vet isn’t available, call an emergency vet. Consulting an expert ensures that any pain relief your pet receives won’t mistakenly cause them harm or create a bigger problem (and a bigger vet bill) down the line.
Keep household medications out of reach of pets
Some acetaminophen poisoning occurs through accidental ingestion. While a child-proof cap is difficult for small human fingers to remove, an unsupervised dog may be able to chew the same bottle open with ease. Be sure to keep all medications, whether they are prescription or over-the-counter, in a safe location out of the reach of both children and pets. Drawers or cupboards that shut tightly can help prevent pill bottles from ending up where your dog or cat can find them.
If you ever drop a pill when you are getting medication for yourself, it is very important to locate and retrieve it so it is not found later by a curious pet. Remember, an average sized adult cat only needs to ingest a part of a single pill to be at risk of serious health complications.
Leave it! Training tips for safer pets
Did you know you can bond with your pet and help keep them safe at the same time? Training games that work on improving your pet’s impulse control–such as teaching a cue like “leave it” or “wait”–are a fun and effective way to teach them to pause before immediately trying to swallow things that land on the floor. A positive-reinforcement trainer can show you how to make sure the games feel fun to your pet, so they are motivated to listen when it counts. When practiced, skills like these can buy you the life-saving seconds you need to confiscate a fallen pill.
If you know or suspect that your pet has ingested acetaminophen, call your family veterinarian right away or bring your pet to our hospital at Animal Emergency Care. #AECprevents
Sources:
https://www.aspca.org/news/official-top-10-toxins-2024
https://veterinarypartner.vin.com/default.aspx?pid=19239&id=4952627
https://veterinarypartner.vin.com/default.aspx?pid=19239&id=12509433
