Ivermectin intoxication in three dogs with and without MDR1 gene mutation caused by vermicide paste licensed for use in horses.

摘要

This study was conducted to determine the effect of ivermectin vermicide paste licensed for horses (Ivomec PReg. and EqvalanReg. in Germany and Switzerland, respectively) on dogs with (n=1) or without (n=2) MDR1 gene mutation. Results revealed that the dogs with intact MDR1 gene and treated with 2.5-5 mg/kg ivermectin had bilateral mydriasis, visual deficits and uncontrolled facial muscular contractions. One Collie dog given 150-300 micro g/kg ivermectin and had a homozygous MDR1 gene mutation showed severe symptoms of apathy, tremors, hypersalivation, and coma with phases of spasm and screaming. It is concluded that dogs with intact MDR1 gene show mild symptoms of toxicity which subside after two to three days. However, dogs with homozygous MDR1 gene mutation are severely affected with ivermectin at >=0.2 mg/kg.