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The Effects of Over the Counter Pain Medication for Dogs

The Effects of Over the Counter Pain Medication for Dogs

Nov 03, 2021

Unlike humans, pets cannot just tell you where it hurts. It take an attentive owner to be able to determine if your pet is not feeling well. But before you reach into your cupboard to make it all better, there are a number of things you should know about over the counter pain medication for dogs.

Not to scare you (though it is scary), human meds can be very dangerous and potentially fatal to dogs. These include common pain relievers such as ibuprofen, aspirin and acetaminophen. It sounds reasonable that if the pill worked for you, it should also work for your four-legged-friend. Though some pain relief may be evident, there are several underlying issues with over the counter pain medication for dogs.

Non-Steroidal Anti-Inflammatories

Also called NSAIDs for short, aspirin, baby aspirin, ibuprofen and naproxen work in the same general fashion to relieve swelling, stiffness, joint pain or for recovery after a medical procedure..

These compounds inhibit an enzyme called “cyclooxygenase.” This enzyme is responsible for the production of prostaglandins that promote inflammation, fever and pain. Reducing prostaglandins means less of the bad stuff in humans.

Prostaglandins are also responsible for maintaining adequate blood flow to the kidneys. It also produces the mucus that lines the gastrointestinal tract as protection from stomach acid and normal blood clotting.

Aspirin has known uses as a blood thinner, which is also necessary for some pets with excessive clotting. The risks outweigh the benefits if you intend to administer aspirin without veterinary approval. The drug is not eliminated as quickly by all animals and can lead to serious bleeding disorders amongst other things.

Use of human NSAIDs in dogs can lead to:

  • Intestinal problems
  • Loss of appetite
  • Bleeding disorders
  • Kidney or liver failure
  • Potential fatality


Tylenol is the most common name brand of acetaminophen. Though it serves to alleviate pain, when used as an over the counter pain medication for dogs, acetaminophen has a number of harsh side effects. Liver cells can be destroyed and kidneys damaged. These are the two main organs that filter compounds through the body. Hemoglobin is responsible for carrying oxygen to the blood. Acetaminophen converts hemoglobin to methemoglobin, which infringes upon this delivery system preventing oxygen from reaching vital organs. Blood lacking hemoglobin is brownish rather than red.

Cats lack a certain protein in the liver, which is necessary to metabolize the medication. Acetaminophen can be fatal to cats, even in small doses.

Overdoses of acetaminophen are often accidental or the result of a pet gaining access to the medicine cabinet. Some signs of acetaminophen toxicity in dogs includes;

  • Brownish/grey gums
  • Labored breathing
  • Swollen face, neck or limbs
  • Hypothermia
  • Vomiting
  • Jaundice

Opioids (Prescription Only)

This is a classification of drugs that are not available over the counter for human or animals. In some cases opioids are offered to pets as a pain reliever or in conjunction with a surgical procedure much like that of humans. Opioids such as morphine, buprenorphine and ketamine are often a part of the pre-surgical cocktail to induce sedation. They may also be administered post-op by a veterinarian. These three substances are typically administered via injection and are rarely sent home with a pet. Buprenorphine may be administered sublingually and is not uncommon as a prescription following a medical procedure.

Human prescribed opioids such as Vicodin, Percocet and Hydrocodone contain varying levels of acetaminophen and should not be used off-label for pets, especially cats. Tramadol is a cross-over opioid, which may be prescribed by a veterinarian. Liquid hydrocodone can also be administered with correct dosage. There are a number of potential side effects for use of opioids in pets, especially if given incorrect dosages.

  • Constipation
  • Mood changes
  • Resilience
  • Respiratory distress
  • Confusion
  • Excessive drooling
  • Tremors
  • Loss of appetite
  • Vomiting
  • Decreased heart rate

Dog Specific Pain Meds

There are several veterinary approved pain medications, specifically designed for dogs. Some of the most popular NSAIDS are:

  • Rimadyl (carprofen)
  • Deramaxx (deracoxib)
  • Previcox (firocoxib)
  • Metacam (feloxicam)

Most veterinarians will recommend blood work every six months or more for pets who are regularly taking NSAIDs. Pre-screening blood work may also be required. This is important to evaluate liver function as even NSAIDs specific to pets may have adverse effects. Liver toxicity can present itself quickly within the first three weeks of an NSAID regimen. General side-effects are similar for both pet-prescribed and human over the counter pain medication for dogs. Because potential severe side-effects do exist, there is some controversy about their use within the veterinary industry.

Alternatives to Over the Counter Pain Medication for Dogs

Just like in humans, there are holistic approaches to medical treatments for animals. Many pet owners have looked to Eastern Medicine for options in acupuncture and massage therapy. Supplements such as omega 3 fatty acids, glucosamine, chondroitin, pure CBD hemp oil have shown noted benefits for coping with pain in both humans and dogs.

According to recent report by the World Health Organization, CBD was found to be safe and well tolerated by both humans and animals. This makes CBD a good option if you do not have veterinarian prescribed medications on hand, or are looking to avoid potential side-effects associated with both human and veterinary over the counter pain medications for dogs. It is important to use pet formulated CBD hemp oil products to ensure there are no added ingredients, which could be harmful to your pet. As always, you should inform your veterinarian when starting any new supplement regimen.