The petroleum distillates in motor oil can cause a lot of harm to a dog that accidentally ingests it by coating the digestive tract and killing the tissues. Symptoms are treatable if the dog is taken to a vet quickly. Dog owners must pet-proof their homes so animals cannot get into harmful or toxic substances used around the house and garage.
Dogs who have ingested motor oil may seem lethargic. Lethargy in dogs will cause them to be inactive, depressed and unwilling to follow commands. They also may have loss of appetite.
Dogs who have ingested motor oil will have trouble walking and will stagger in a uncoordinated fashion. In severe cases, a dog may suffer temporary-to-permanent paralysis in his hind legs.
One of the most severe and certain signs that your dog has ingested motor oil is digestive upset. This begins with drooling and head shaking and progresses to frequent vomiting and diarrhea, which lead to dehydration.
Without veterinary treatment your dog may lapse into a comma and die. Do not attempt to induce vomiting in a dog who may have ingested motor oil -- if your dog gags on the vomit, the oil will get into his lungs and cause aspiration pneumonia, a fatal, untreatable condition.