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Due to the novel Covid 19 virus, the situation nationally and within the state of Washington is changing daily but at this time we are working hard to maintain normal MDR1 testing operations.  We plan to continue to run weekly tests with batches beginning on Mondays and results emailed on Fridays. Any updates will be posted here. 

 We are sorry for any inconvenience but we appreciate your patience as we all work through this trying time

Multidrug Sensitivity in Dogs

Many herding breed dogs have a genetic predisposition to adverse drug reactions involving over a dozen different drugs. The most serious adverse drug reactions involve several antiparasitic agents (ivermectin, milbemycin and related drugs), the antidiarrheal agent loperamide (Imodium), and several anticancer drugs (vincristine, doxorubicin, others). These drug sensitivities result from a mutation in the multidrug resistance gene (MDR1 gene). At Washington State University's College of Veterinary Medicine you can test your dog for multidrug sensitivity and prevent serious adverse drug reactions. We can work with your dog’s veterinarian to find appropriate drug doses or alternative drugs for your dog based on results of MDR1 testing.

The Partnership for Preventive Healthcare, is an initiative jointly sponsored by the American Animal Hospital Association and the American Veterinary Medical Association. Together the two associations offer a set of Canine and Feline Preventive Healthcare Guidelines. One of the important recommendations is that dog owners use genetic testing—like the MDR1 test —as part of an overall healthcare plan for their pets.


Harmonization of Genetic Testing for Dogs Goal: Improve standardization of, and access to, robust genetic testing to support health improvements and a sustainable future for healthy dogs. DogWellNet Website
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