Multidrug Sensitivity: What You Need to Know

Test puppies. If you don’t know the parents’ status or if one parent is known to have the mutation, you should have your puppy tested. In a perfect world, the breeder will have already tested the puppy and will provide you with results to give to your veterinarian.

Testing can be done through your veterinarian or by mail. Test kits are available from WSU’s Veterinary Clinical Pharmacology Lab. You’ll receive a kit and instructions on how to swab the inside of the lips to acquire a DNA sample. There’s no charge to request a kit, but it costs $70 to send in a sample for testing. (The cost drops to $60 per sample if you send in five or more.)

Test results. Your dog will be identified as having two normal copies of the gene, a normal copy and a mutant copy, or two mutant copies. If your dog has two mutant copies of the gene, he is sensitive to the drugs listed above, and if he has one mutant copy of the gene, he may be sensitive to these drugs. In either case, you should notify your veterinarian.

Identify your dog. If you know that your dog has the MDR1 gene mutation, it’s a good idea to add a tag to his collar noting this status. That way, a shelter or veterinarian will know to take precautions with any treatments.

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