A growing number of pets are being accidentally poisoned, and prescription medicines are largely to blame, The Wall Street Journal reports.

The American Society for the Prevention of Cruelty to Animals (ASPCA) reports it received more than 180,000 calls about poisonous substances last year, up 7 percent from 2011. Since many pet owners rush poisoned pets to their veterinarian instead of calling a hotline, the number of accidental poisonings may be higher, the article notes.

Prescription medications for humans have accounted for the majority of calls about accidental poisonings for the past five years, increasing 2 percent last year to more than 25,200 calls. Pet owners made almost 18,500 calls about over-the-counter medications and supplements, up 2.8 percent from the previous year.

While insecticides and rodenticides are the most deadly household items for pets, common human medicines can also be fatal, depending on the pet’s weight, how much the pet consumes, and the strength of the medicine. “One acetaminophen will kill a cat,” Kevin T. Fitzgerald, a veterinarian with VCA Alameda East Veterinary Hospital in Denver, told the newspaper.

Last year, calls about prescription painkillers increased 63 percent, while calls about antidepressants rose 47.5 percent. “More and more people are on these drugs, and dogs find them on the nightstand,” Dr. Fitzgerald said.

The fatality rate among pets from accidental poisoning appears to be low, at 0.2 percent of cases, according to Tina Wismer, Director of the ASPCA’s Animal Poison Control Center. She notes the center does not know the outcome of each call, so the rate might be higher. Dogs are more likely than cats to be accidentally poisoned. Labrador Retrievers accounted for almost 14,000 calls to the center.

To limit pets’ access to dangerous substances, keep medications in a secure location such as a medicine cabinet, and take the medication when the pet isn’t nearby.