Human medications cause a large number of drug-related emergencies seen in senior pets. Whether your senior pet breaks into your medicine cabinet or you give them a human medication in a well-intentioned attempt to alleviate a health concern, the consequences can be devastating. Never medicate your senior pet without consulting your veterinarian, and always ensure your medications are secured in a safe place inaccessible to your pet. Below are the most common human medications that cause problems for senior pets.

#1: Non-steroidal anti-inflammatory drugs (NSAIDs) and senior pets

NSAIDs include common drugs such as ibuprofen (e.g., Advil and Motrin) and naproxen (e.g., Aleve). Dogs can take certain NSAIDs, but the majority of human-approved NSAIDs are not safe for senior pets. The sweet coating on many products makes these drugs attractive to pets, with the result that NSAIDs are the deadliest human drug for all senior pets. When pets ingest NSAIDs, damage to their gastrointestinal lining is the most common problem, as well as kidney or liver failure. Senior cats are especially susceptible to kidney damage. NSAID toxicity signs include vomiting, diarrhea, lethargy, seizures, and collapse.

#2: Acetaminophen and senior pets

Acetaminophen (e.g., Tylenol) is a relatively safe medication for humans, but can cause severe issues for pets. Senior cats metabolize the drug poorly and are more susceptible to acetaminophen poisoning. After ingesting acetaminophen, cats develop methemoglobinemia, which results in their red blood cells’ inability to carry oxygen. Clinical signs include lethargy, swelling of the face or paws, difficulty breathing, vomiting, and pale or blue mucous membranes. Senior dogs are not as sensitive to acetaminophen toxicity as cats, but can still be affected if they ingest the drug, typically developing liver failure. Methemoglobinemia can also occur if enough of the drug is consumed. Signs include lethargy, decreased appetite, vomiting, yellowish mucous membranes, incoordination, and seizures.

#3: Beta blockers and senior pets

Beta blockers, such as propranolol, timolol, and sotalol, are commonly prescribed to treat high blood pressure. These medications can be safe in pets when used at the appropriate dose, but two to three times the high end dose can cause serious complications. Beta blockers decrease blood pressure by blocking epinephrine’s effects, causing the heart to beat more slowly, with less force. Senior pets who overdose on beta blockers experience severe hypotension and decreased heart rate, causing poor perfusion to their organs, especially the kidneys. Signs include vomiting, weakness, and collapse.

#4: Antidepressants and senior pets

Selective serotonin reuptake inhibitors, such as Cymbalta, Effexor XR, Prozac, Reconcile, and Zoloft, can result in problems at therapeutic doses. Cats tend to find Effexor XR especially tantalizing, and often eat the entire pill. Signs include lethargy, decreased appetite, and sedation. In severe cases, a condition called serotonin syndrome, which causes hyperactivity in senior dogs, can occur. The syndrome can also affect senior cats, who will tend to be sedate, exhibit dilated pupils and panting, and may have tremors and seizures if the dose is extremely high. 

#5: Amphetamines and senior pets

Medications such as Concerta, Adderall, and Ritalin are commonly prescribed for Attention Deficit Hyperactivity Disorder (ADHD). These drugs cause overstimulation of the nervous system. Clinical ADHD signs can affect several body systems:

* Central nervous system — Agitation, dilated pupils, tremors, seizures

* Cardiovascular — Increased heart rate, high blood pressure

* Gastrointestinal — Drooling, vomiting, diarrhea

* Respiratory — Panting

#6: Anti-anxiety medications and senior pets

Benzodiazepines, such as Xanax, Klonopin, Ativan, and Valium, are prescribed as anticonvulsants and muscle relaxants, and to help reduce anxiety in people. Some benzodiazepines are safe for pets, but an overdose can result in signs that include sedation, incoordination, aggression, agitation, vomiting, and respiratory distress.

#7: Pseudoephedrine and senior pets

Pseudoephedrine, an oral decongestant used in humans, stimulates the nervous and cardiovascular systems. At correct dosages, the drug can also treat urinary incontinence in dogs. In overdose cases, common signs include hyperactivity, tremors, panting, and dilated pupils.

Pets are curious and can be crafty, filching items you thought were out of their reach. If your senior pet ingests human medication, immediately contact your veterinarian or Animal Poison Control.

If your pet has a condition causing a poor quality of life, contact Lap of Love’s telehospice service to see if they could benefit from veterinary hospice care. If you feel their quality of life is no longer acceptable, contact a Lap of Love veterinarian in your area to discuss in-home euthanasia.