Effective June 16, 2026
Not a substitute for veterinary care
MDR1Dog is an informational reference about the canine MDR1 (ABCB1) gene. It is not a veterinary clinic and does not provide veterinary advice, diagnosis, or treatment. Nothing on this site creates a veterinarian–client–patient relationship. It does not replace an examination by, or the professional judgement of, a licensed veterinarian who knows your individual dog.
Always talk to your vet first
Do not start, stop, or change any medication for your dog based on this site. Always discuss any medication decision with your veterinarian before acting. Your vet knows your dog's full history, current condition, and — if it has been tested — its MDR1 genotype. We know only what published research says about drugs in general.
This is not for emergencies
If your dog has been given a medication and is showing concerning signs — such as tremors, disorientation, loss of muscle control, or any sudden change — treat it as an emergency and contact a veterinarian or emergency veterinary clinic immediately. Do not use this site in place of urgent professional care.
Accuracy and sources
We source drug classifications and breed frequencies from primary veterinary references, principally the Washington State University Veterinary Clinical Pharmacology Laboratory, and we record a last-verified date for each. Even so, veterinary science evolves, sources can change, and errors are possible. We make no warranty that the information is complete, current, or applicable to your specific dog. See our methodology and sources.
No liability
To the fullest extent permitted by law, MDR1Dogand its operators are not liable for any loss, injury, or harm arising from reliance on information provided here. You use this site at your own discretion and remain responsible for your dog's care in partnership with a licensed veterinarian.
Affiliate links
Some links to DNA-test products may, in future, be affiliate links from which we earn a referral fee at no extra cost to you. We disclose this clearly where it applies and earn nothing from the non-affiliate WSU VCPL test option. See our terms.