Multidrug resistance 1

Multidrug resistance 1 is a hereditary disease that makes affected dogs particularly sensitive to certain drugs (ivermectin, loperamide and many others). Exposure to these drugs can lead to severe neurological symptoms such as hypersalivation, ataxia, blindness, tremor, respiratory distress and even death. The cause of the disease is a mutation in the gene that produces P-glycoprotein, whose role is to transport and eliminate certain drugs.  The disease is inherited in an autosomal recessive way, meaning that affected individuals must inherit the mutation in both copies of the gene. However, it is known that even carriers can have a mild adverse reaction after administration of these drugs.