05/29/2026
✨🐾 Fun Fact Friday! 🐾✨
Did you know that some dogs carry a genetic mutation called ABCB1 -Delta (formerly known as MDR1) that can make them sensitive to certain medications?
This mutation is most commonly found in breeds such as Collies, Australian Shepherds, Shetland Sheepdogs, and related breeds. Dogs with this mutation may have difficulty processing certain drugs, which can lead to serious side effects.
One medication often associated with this mutation is ivermectin. While high doses of ivermectin can be dangerous for dogs with the ABCB1 mutation, the good news is that Heartgard® contains a very low dose of ivermectin and is considered safe for dogs, even those with the mutation, when given as directed.
⚠️ It’s important to remember that ivermectin products intended for livestock or ivermectin given by itself should never be administered to your dog unless specifically prescribed and dosed by your veterinarian.
Have questions about your dog’s breed, genetic testing, or parasite prevention? We’re happy to help!
