Published dose range
Published guidance for dogs: 500-1000 mg per dog, every 12h.
Source: Merck Veterinary Manual →Used in some heart conditions (DCM) under vet guidance; harmless margin but the underlying disease needs a vet.
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.