Common allergy medications pose serious risks to pets

Tiffany Day, a travel nurse, and her labrador retriever mix Luna had been in Illinois on an assignment but finally was able to travel home to Illinois. After their car ride to Illinois, Day realized that she was missing a few items and needed to go to the store. Day left Luna, along with her open travel bag she stored in the bathroom and headed to the store to get the items she needed. However, when she arrived back home, she did not expect to find a chewed up and open allergy medication bottle on the floor.

"I'm a travel nurse, and Luna and I had just gotten home from an assignment in Illinois, and I was exhausted from the drive. I thought, 'she's tired, she won't get into anything' and I ran out for a quick trip to the store. When I got home, there was a chewed-open bottle of allergy pills on the floor, and it was clear Luna had ingested some of the mediation,” explained Day, in an organizational release.¹

“I'd never heard there was a problem with giving your pets allergy pills like Benadryl, so I wasn't too worried. As the night progressed, however, she began barking at nothing, swaying, and walking into walls. It was then I knew she needed a veterinarian," she continued.

According to the release, antihistamines provide relief to those suffering from allergies, but medications like Benadryl contain diphenhydramine, which can be dangerous and in some cases, even deadly to pets if the dose is too high.¹ For pets that ingest these medications, intentionally or not, pet parents should consult with a veterinarian before giving pets any human medication or immediately after if pets accidentally ingest something that could be toxic.

Luna, a labrador retriever mix, ingested her owner's allergy medication (Image courtesy of Pet Poison Helpline)

Day then took Luna to the Roadrunner Veterinary Emergency & Specialty Hospital in Algodones, New Mexico, where the team had her call the Pet Poison Helpline to develop a treatment plan based on Luna’s exposure and situation.

"Many people give their pets human allergy medications that contain diphenhydramine," explained Renee Schmid, DVM, DABT, DABVT, a senior veterinary toxicologist and director of veterinary services at Pet Poison Helpline.¹ "In most cases, a small dose is safe for your pets. If the dose is too high, however, it can result in some very dangerous reactions, including agitation or lethargy, aggression, abnormal heart rate, abnormal blood pressure, vomiting, diarrhea, and even seizures and respiratory depression with extremely large ingestions. In severe cases, such as with Luna's situation, the ingestion could be fatal."

Upon arrival to the hospital, Luna had developed mild signs and was administered an antiemetic to keep her from vomiting, placed on intravenous fluids, and was sedated due to agitation. The hospital was then advised to administer additional medications for tremors or seizures if they were to develop. Luna spent the night at the hospital and was monitored closely to be sure she did not develop any other severe signs and due to the care she received, Luna went home the follow day to continue to recuperate.

Although Luna made a full recovery from her diphenhydramine exposure, she developed immune-mediated thrombocytopenia (IMTP), a known but likely unrelated condition, which ultimately led to her passing away. According to Schmid, IMTP is a condition where the immune system attacks its own platelets which can lead to premature destruction of the platelets.¹

"Even though Luna later passed from a different condition, I wanted to share her allergy medication story," concluded Day. "If telling her story can help even one other pet, it will be worth it. You have to be on your game at all times. Keep all medications, even those you think are safe for your pets, away from reach. You don't think they'll get into it, but they will."

Reference

Common Allergy Medication Can Be Deadly to Pets. News release. Pet Poison Helpline. August 7, 2024. Accessed August 7, 2024. https://prnmedia.prnewswire.com/news-releases/common-allergy-medication-can-be-deadly-to-pets-302215797.html