Is Ivermectin Safe For Lactating Dogs
Ivermectin is helpful for treating lice, mites, myiases and intestinal worms in cattle, while veterinarians primarily use the drug to prevent heartworm in dogs. While the drug usually is administered orally or via injection when treating.
Lactation/breastmilk Ivermectin Levels and Effects while Breastfeeding Summary of Use during Lactation Limited data indicate that ivermectin is poorly excreted into breastmilk after oral administration. Amounts ingested by the infant are small and would not be expected to cause any adverse effects in breastfed infants over 7 days of age. 
In these dogs, ivermectin can pass directly to the brain and be toxic or even lethal. Sensitivity to the drug can also be seen in dogs or puppies that have overdosed on a similar medication in the past. A genetic sensitivity to.
Ivermectin used at dosages used for heartworm prevention is generally safe for these dogs. However, the drug should not be used at higher doses for dogs that may possess the MDR1 gene mutation. There is a test that can be performed to check for the gene mutation.