Acetaminophen

What is acetaminophen?

Acetaminophen, also known as paracetamol, is an analgesic (pain reliever) and fever-reducing medication. It is used to treat pain and fever in dogs. Acetaminophen should only be given under the direction of a veterinarian.

It is used “off label” or “extra label” in some veterinary species, including dogs, rabbits, miniature pigs and some rodents. Many drugs are commonly prescribed for off-label use in veterinary medicine. In these instances, follow your veterinarian’s directions and cautions carefully. Avoid any use in cats and ferrets as it is potentially fatal in these species. 

How do I give my pet acetaminophen?

Acetaminophen comes in capsule, tablet, and liquid suspension forms. It may be combined with other pain medication.

• Capsules, tablets, and liquid suspensions are given orally (by mouth).
• This medication can be given to your pet with food or on an empty stomach. 
• Give this medication to your pet for the entire time prescribed by your veterinarian, even if it appears that your pet is feeling better.

This medication will take effect quickly, in about 1 to 2 hours. This medication is short-acting, meaning that effects should stop after 24 hours but may be prolonged in pets with kidney and/or liver disease.

What if I miss giving my pet the medication?

Give the missed dose as soon as you remember and then continue with the regular dosing schedule. If it is almost time for the next dose, skip the missed dose and continue with the regular schedule. Do not give the pet two doses at once.

Are there any potential side effects from acetaminophen?

Acetaminophen may cause the following side effects:

• reduced appetite, vomiting, or diarrhea

The following reactions are rare, but if they occur, contact your veterinarian immediately:

• an allergic reaction such as irregular breathing, rash, fever, or puffiness and swelling around the face
• signs of liver toxicity such as jaundice (yellowing of skin, whites of eyes, and/or gums), bloated painful abdomen, profuse vomiting and/or diarrhea, no appetite, black tarry stools, and/or bleeding

Drug sensitivities can develop over time with repeated exposure. Your pet may have no reaction after the first few doses, but may develop a sensitivity later. It is important to watch for signs of an allergic reaction over the entire course of treatment.

Are there any risk factors for this medication?

NEVER USE in cats or ferrets as it is potentially fatal even at miniscule doses.

AVOID USE in animals with known allergies to any components and in hedgehogs and sugar gliders (unknown safety in those species).

USE WITH CAUTION:

• in pets with liver disease
• in pets experiencing gastrointestinal issues
• in conjunction with other pain medications and fever-reducing drugs

Are there any drug interactions I should be aware of?

Certain medications should be USED WITH CAUTION when given with acetaminophen, including: 

• local anesthetics (e.g., lidocaine)
• chloramphenicol
• phenobarbital and other barbiturates
• penicillin G/procaine
• metoclopramide
• acepromazine
• propylene glycol
• rifampin
• doxorubicin
• cholestyramine
• verdinexor

Be sure to tell your veterinarian about any medications (including vitamins, supplements, or herbal therapies) that your pet is taking before starting any new treatment.

Is any monitoring needed with this medication?

• Your veterinarian may prescribe two different medications, and a drug interaction may be anticipated. In this case, your veterinarian may vary the dose and/or monitor your pet more closely.
• Your veterinarian may schedule follow-up visits for monitoring. In this case, follow your veterinarian’s directions.

How do I store acetaminophen?

• Store medication at room temperature. 
• Keep capsules away from moisture.
• Keep medication out of reach of children and pets.

What should I do in case of emergency?

If you suspect an overdose or an adverse reaction to the medication, call your veterinary office immediately. If they are not available, follow their directions in contacting an emergency facility.