405 Heron Drive Suite 200
Swedesboro, NJ 08085
Ph 800.331.8272

Human Medications That Are Toxic to Pets

It's not uncommon for veterinarians to turn to human medications to treat pets who are suffering from certain health conditions. But just because pets can take some human medications doesn't mean that all medications made for humans are likewise safe for pets.

In fact, some of the most-commonly prescribed human medications can be dangerous and even potentially deadly when ingested by animals.

Top 10 Medications to Keep Away from Your Pet

NSAIDs—Non-steroidal anti-inflammatory drugs, or NSAIDs, are common, everyday drugs found in most households. This class of drug includes prescription and over-the-counter forms of ibuprofen, naproxen, and others. Popular brand names include Motrin, Naprosyn, Advil, and Aleve. NSAIDs are some of the most dangerous drugs for pets to ingest.

Just one or two pills can cause dogs and cats to birds, ferrets, hamsters, and other small animals to suffer serious stomach and intestinal ulcers and in some cases, even kidney failure and liver toxicity.

Acetaminophen—Acetaminophen is another over-the-counter medication found in most homes, with the most recognizable being the brand Tylenol. The problem with this medication is that it often is considered “safe” because even children can take it. But should your pets ingest it, they could suffer from serious health problems.

In cats, acetaminophen can cause damage to red blood cells, reducing their ability to carry oxygen through the body. In dogs, the drug can cause liver failure. Dogs also can suffer from extensive damage to the red blood cells, but they require a significantly larger dose of acetaminophen than cats.

Birth Control Pills—Dogs often can mistake birth control containers for toys, but if they swallow a large number of the pills, they can get very ill. Estrogen and estradiol have been shown to cause bone-marrow suppression in dogs, cats, and particularly in birds.

Antidepressants—It is not uncommon for a veterinarian to prescribe an antidepressant medication for anxiety-related and behavioral conditions. But while the drugs are safe when administered according to your veterinarian's instructions, too much of these medications can lead to a host of health problems for your pet.

For instance, an overdose of antidepressants can cause serious neurological problems including sedation, loss of coordination, tremors, and even seizures. Common brand names include Cymbalta, Effexor, Prozac, Lexapro, and others.

ADHD/ADD Medications—Medications prescribed for Attention Deficit Disorder (ADD) and Attention Deficit Hyperactivity Disorder (ADHD) usually contain very strong stimulants like amphetamines and methylphenidate, and these chemicals can have serious side-effects if ingested by a pet.

All it takes is a small dose of these types of medications to cause life-threatening problems like elevated body temperatures, seizures, tremors, and heart problems. Common brand names include Ritalin, Adderall, and Concerta.

Benzodiazepines (Sleep Aids)—Benzodiazepines are prescribed to help reduce a patient's stress levels, or to help induce asleep. These types of drugs include Xanax, Ambien, Klonopin, and Lunesta. But sometimes when pets take benzodiazepines, the drugs have a reverse effect in which they cause the pet to become agitated.

In others, the drug can cause severe lethargy, listlessness, incoordination, and slowed breathing. Cats also are prone to suffering from liver damage after ingesting certain types of benzodiazepines.

Cholesterol-Lowering Drugs—Cholesterol-lowering drugs like Lipitor, Crestor, and Zocor now are found in a large percentage of American drug cabinets. While these drugs, which are classified as statins, aren't normally dangerous to pets, they can cause some potentially serious problems if taken over long periods of time.

In most cases, however, your pet will usually suffer from some mild intestinal upset, including vomiting and diarrhea.

Thyroid Hormones—When dogs are prescribed thyroid hormones by their veterinarians, they tend to take much higher doses than a human would take. But this doesn't mean that an overdose can't happen. If a pet ingests a large dose of thyroid hormones, he could suffer from an elevated heart rate, increased aggression, muscle tremors, excessive panting, and nervousness.

Beta-Blockers—Beta-blockers like Toprol, Coreg, Tenormin, and others are prescribed to humans with blood pressure problems. But all it takes is a small dose of these drugs to cause poisoning in cats, dogs, and other household pets. Large doses can result in severe drops in blood pressure that can be life-threatening.

ACE Inhibitors—As in humans, angiotensin-converting enzyme (ACE) inhibitors often are used to treat pets suffering from high blood pressure. Though these medications typically are safe when administered according to your veterinarian's instructions, overdoses can occur should the pet ingest more than their recommended doses. In these cases, the pet can experience a severe drop in blood pressure, dizziness, and weakness.

How to Protect Your Pets from Ingesting Your Medications

Most pets are naturally curious creatures. As a result, if you have prescription medications or take over-the-counter drugs, it is important to keep them out of reach of your pets. Here are some tips to help ensure your pet never ingests your medicine.

  • Never leave your pills on the counter or anywhere a pet can reach them;
  • Never leave your pill bottles within reach of your pet;
  • Pick up dropped pills immediately, before your pet is able to ingest them; and
  • Never give any prescription or over-the-counter medication meant for humans to your pet without first consulting your veterinarian.

If your pet has ingested any medication that was not prescribed for him, be sure to contact your veterinarian immediately.

About the Author

Dr. Evan Ware

Dr. Evan Ware is a veterinary practitioner in Phoenix, Arizona. He received both his undergraduate degree in microbiology and his Doctorate of Veterinary Medicine from The Ohio State University.

Dr. Ware is currently the Medical Director of University Animal Hospital (VCA) and is also the owner of two other hospitals, including Laveen Veterinary Center and Phoenix Veterinary Center. His areas of expertise include orthopedic medicine and surgery, veterinary oncology and chemotherapy, and general and advanced soft-tissue surgery.