10 Human Medications that Poison Our Pets

Dogs and cats are not like humans when it comes to how they metabolize medications. Although some human medications are used in veterinary medicine, the doses are vastly different. Poisonings from human medications can be life-threatening to our pets. Here are the 10 human medications that most commonly poison our pets:

NSAIDS (Ibuprofen, Naproxen)
One of the most common problems we see in pets is toxicity from nonsteroidal anti-inflammatories (NSAIDs), which include ibuprofen (like Advil and some types of Motrin) and naproxen (like Aleve). While these drugs are perfectly safe for us, just one tablet can be toxic for pets. Dogs, cats, birds, ferrets, gerbils and hamsters may develop serious stomach and intestinal ulcers as well as kidney failure if they ingest these.

Acetaminophen (like Tylenol) should never be given to pets, especially cats. Acetaminophen can lead to liver failure, and in large doses, it can create red blood cell damage that causes cells to stop carrying oxygen.

Antidepressants (Effexor, Cymbalta, Prozac, Lexapro)
Although these drugs are occasionally used in pets in low doses, overdoses can lead to serious neurological problems such as sedation, incoordination, tremors and seizures.  Some antidepressants also have a stimulant effect, which leads to a dangerously elevated heart rate, blood pressure and body temperature. Pets, especially cats, seem to like the taste of Effexor and may eat large amounts of pills they find. But just one pill can cause serious poisoning.

ADD and ADHD Medications (Concerta, Adderall, Ritalin)
These and other medications used to treat attention deficit disorder and attention deficit hyperactivity disorder in people contain methylphenidate and amphetamines, which are potent stimulants. These drugs can cause serious side effects in our pets, including seizures, elevated body temperatures, heart problems and life-threatening tremors.

Benzodiazepines and Sleep Aids (Xanax, Klonopin, Ambien, Lunesta)
Although these drugs are intended to reduce anxiety and help people sleep better, they often have the opposite effect in pets. About half of the dogs that ingest sleep aids become agitated instead of sedated. The other half show symptoms of severe lethargy, incoordination and respiratory depression (slowed breathing). Benzodiazepines can also cause liver failure in cats.

Birth Control (Estrogen, Estradiol, Progesterone)
These appear to be a popular item with dogs, as they apparently like how birth control pills are packaged. Fortunately, ingesting small amounts of these medications do not typically cause serious problems for pets. However, the ingestion of large amounts of estrogen and estradiol can cause bone marrow suppression, especially in birds. Dogs and cats that have not been spayed are at an increased risk of side effects from estrogen poisoning.

ACE Inhibitors (Zestril, Altace)
These drugs are used to treat high blood pressure in people and occasionally in pets.  When pets ingest them in low doses, they may only experience mild symptoms. Overdoses, however, usually cause low blood pressure, dizziness and weakness. Depending on the dosage ingested and if your pet has a history of kidney failure or heart disease, your pet may need to be hospitalized for observation and monitoring.

Beta-Blockers (Tenormin, Toprol, Coreg)
Beta-blockers are also used in people to treat high blood pressure, but unlike ACE inhibitors, ingestion of this drug, even in small amounts, may cause serious poisoning in pets. Symptoms of ingestion include life-threatening drops in blood pressure and slowed heart rates.

Thyroid Hormones (Armour Desiccated Thyroid, Synthroid)Dogs, like people, can have low thyroid levels that require supplementation.  Surprisingly, dogs tend to require higher amounts of thyroid medication than people do.  Therefore, accidental ingestion of small amounts of thyroid medication usually will not cause problems. However, ingesting large amounts of thyroid medication can cause muscle tremors, nervousness, panting, aggression and rapid heart rates in dogs and cats.

Cholesterol-Lowering Agents (Lipitor, Zocor, Crestor)
Cholesterol-lowering medications, often called statins, typically cause mild vomiting and diarrhea when our pets ingest them. Serious side effects come from long-term ingestion, not one-time ingestion.

My pet just ate my medication! What do I do?
If your pet eats pills, don’t wait for symptoms to appear. Early initiation of treatment is important for preventing toxicity. Remember to bring the bottle or package with you when you seek emergency care so the veterinarian can identify the type and strength of the medication. This information helps your veterinarian decide what kind of treatment is needed.

If you’d like to learn more about medication toxicity in pets, or if your pets ever accidentally ingest something they shouldn’t eat, contact I-20 Animal Medical Center.