Chocolate is toxic to pets but intoxication problems are typically seen in dogs. Cats just don’t seem to be interested in consuming chocolate, though intoxication is possible if they do. Ingestion of chocolate can lead to acute gastrointestinal upset, heart problems and neurologic complications.
The toxic components of chocolate are caffeine and theobromine. The fat in chocolate can cause problems as well. Caffeine and theobromine are methylxanthines and are typically in highest concentrations in bakers chocolate followed by semisweet chocolate, milk chocolate and white chocolate.
The first noted clinical signs are often vomiting and diarrhea. Dogs may also be restless, hyperactive and wanting to drink large amounts of water. Dogs may have an elevated temperature and fast heart rate. In cases of severe intoxication signs can include tremors, heart failure, seizures and death.
Treatment may involve making the dog vomit the chocolate (not appropriate in every case – proceed only under veterinary supervision) and symptomatic treatment as indicated. In cases of mild intoxication a bland diet and medication to address stomach upset may be all that is indicated. In cases of severe intoxication it may be necessary to place animals on IV fluids, anti emetics, stomach protectants, anti seizure medications and heart medications. Diagnostics that may be appropriate in severe cases include complete lab work, blood pressure checks, and an ECG to check heart rate and rhythm.
Another consideration with chocolate intoxication is other compounds the dog may have ingested – wrappers, containers, fat, etc. These can cause their own problems so be sure to give your veterinarian an accurate as possible account of what was eaten.
A good resource for information on all types of intoxications is the ASPCA web site.