Published dose range
The published veterinary reference range for loperamide in dogs is 0.08-0.1 mg per kg of body weight, given every 8-12h, max 2 days.
Source: Veterinary Partner (VIN) →DANGER: MDR1-mutation breeds (Collies, Australian Shepherds, Shelties, related herding breeds) can suffer severe neurotoxicity. Do not use in herding breeds without a vet MDR1 test.
Skip it or ask a vet first if
MDR1 breedsdiarrhea with bloodsuspected toxin ingestioncats
If you think you overdosed
Call the Pet Poison Helpline: 855-764-7661 or ASPCA Poison Control: 888-426-4435. Both are staffed 24/7 by veterinary toxicologists.