For the third year in a row, human medications, including dropped pills, have sickened more pets in the United States than any other toxin.
The American Society for the Prevention of Cruelty to Animals released the list of last year's top 10 causes of pet poisonings Friday.
Over-the-counter medicines with ibuprofen and acetaminophen, antidepressants and medicine for attention deficit hyperactivity disorder topped the list.
About a quarter of the 168,000 calls received last year by the ASPCA hotline in Urbana, Ill., involved pets that had swallowed human drugs, said Tina Wismer, a veterinarian and the center's senior director of veterinary outreach and education.
The Pet Poison Helpline in Minneapolis, run by SafetyCall International, has handled more than 750,000 calls since 2004, said Justine Lee, a veterinarian and the helpline's associate director of veterinary services. She estimated half their calls involve human medicine.
Pet owners won't always know what their animals have gotten into -- they just know they are showing symptoms like lethargy, vomiting, depression, seizures or refusing food.
A dog who has swallowed pills to treat attention deficit hyperactivity disorder will get agitated. What happens when a pet gets hold of birth control, Viagra and Rogaine pills?
"Luckily, birth control pills today have very small amounts of estrogen in them. We use Viagra for dogs with pulmonary hypertension, and it was originally marketed to regulate blood pressure. Rogaine can be very dangerous, especially in cats, and can cause heart failure," Wismer said.
One aspirin or one heart pill probably won't kill a pet, but a month's supply, a big bunch of grapes, a few bars of dark chocolate or a single lily could.
Insecticides, rodenticides, people food, veterinary medications, chocolate, household toxins, plants, herbicides and outdoor toxins, such as like antifreeze and fertilizers, round out the top 10.
About an ounce of milk chocolate per pound, but only an eighth of an ounce of really dark chocolate per pound could prove deadly for a dog, Wismer said.