In your medicine cabinet you probably have a whole host of prescription and over the counter medications that while safe for humans can be extremely dangerous for pets. The following pharmaceuticals should be kept out of reach of pets and children.
1. NSAIDs
Advil, Aleve, and Motrin are among the most common non-steroidal anti-inflammatory (NSAID) medications and can be purchased without prescription. Ibuprofen or naproxen is the active ingredient in these NSAIDs and even a single dose can be harmful to your pet. Stomach and intestinal ulcers and kidney failure are among the more serious effects.
2. Acetaminophen
Tylenol is likely the most popular analgesic on the market today and you’d be hard pressed to find a household without Tylenol or a generic form of acetaminophen. Safe for humans and even children, acetaminophen has become a go-to for aches and pains associated with colds or other minor illnesses but one regular strength pill can damage your cat’s red blood cells and interfere with her ability to transport oxygen. In dogs, acetaminophen overdose can cause liver failure and red blood cell damage.
3. Antidepressants
Small doses of antidepressants like Effexor, Cymbalta, Prozac, or Lexapro are sometimes diagnosed to pets with anxiety problems, but antidepressant overdoses can have serious side effects. Neurological problems including sedation, lack of coordination, tremors, and seizures as well as stimulant effects like elevated heart rate, blood pressure, and body temperature can be caused by antidepressants in pets. Notably, cats have been known to enjoy the taste of Effexor but just one pill is enough to poison your cat.
4. ADD/ADHD Treatments
ADD and ADHD are seemingly a growing concern for parents in today’s generation. While children, and sometimes adults, are often treated harmlessly with medications like Concerta, Adderall, and Ritalin, these strong stimulants contain ingredients like amphetamines and methylphenidate. Small doses of these medications can be life threatening for pets and may cause seizures, elevated body temperatures, and heart problems.
5. Benzodiazepines/Sleep Aids
Xanax, Klonopin, Ambien, and Lunesta are prescribed to limit anxiety and assist people with sleeping but in pets these drugs have the opposite effect. Pets exposed to benzodiazepines and other sleep aids become agitated and in larger doses severe lethargy, lack of coordination, and slowed breathing results. Cats are also susceptible to liver failure with some benzodiazepines.
6. Birth Control
Birth control pills contain natural hormones including estrogen, estradiol, and progesterone. Small doses of birth control pills are usually harmless to pets, but in larger doses birth control pills can suppress bone marrow, especially in birds. Moreover, non-spayed female pets that come in contact with birth control pills are even more at risk of estrogen poisoning.
7. ACE Inhibitors 
Angiotensin-converting enzyme (ACE) inhibitors such as Zestril and Altace are used to treat high blood pressure, sometimes even in pets. However, ACE inhibitor overdoses lead to dangerously low blood pressure, dizziness, and weakness. In fact, contact with these medications is not particularly serious but if your pet is already suffering from a kidney or heart problem, ingestion of ACE inhibitors can be more serious. If you suspect your pet has accidentally ingested an ACE inhibitor, monitor him closely and visit the veterinarian immediately if you notice any strange side effects.
8. Beta-Blockers
Tenormin, Toprol, and Coreg are common beta-blockers that are used to treat high blood pressure. However, unlike ACE inhibitors, beta-blockers can cause serious problems in pets. Overdoses of beta-blockers can be life-threatening as they can cause considerable drops in blood pressure leading to a very slow heart rate.
9. Thyroid Hormones
Armour desiccated thyroid and Synthroid are hormones prescribed for individuals with underactive thyroids. While these medications are also used in dogs, they are usually prescribed at much higher doses. As such, accidental ingestion of thyroid hormones is likely not going to cause serious side effects. However, large overdoses in cats and dogs have been shown to cause muscle tremors, nervousness, panting, increased heart rate, and excessive aggression.
10. Cholesterol Maintenance Medication
Finally, cholesterol lowering agents like Lipitor, Zocor, and Crestor, known as statins, are common for individuals with high, seeming uncontrollable cholesterol. Statin overdoses can cause minor vomiting and diarrhea and serious side effects are associated more with long term use.