In most chocolate compounds theobromine is the predominant toxic component, and caffeine is present in much lower concentrations. For animals that have ingested chocolate products made in the home or in bakeries or produced as a prepackaged mix, it may be difficult to identify the exact amount and type of chocolate used. In these cases estimate the methylxanthine dose based on a worst-case scenario. 3 Clinical signs usually occur within six to12 hours of ingestion. 3 Initial signs include polydypsia, vomiting, diarrhea, bloating, and restlessness.
Signs progress to hyperactivity, polyuria, ataxia, tremors, and seizures.
3 Other effects include tachycardia, premature ventricular contractions, tachypnea, cyanosis, hypertension, hyperthermia, and coma. 3,5 Less commonly, bradycardia and hypotension may occur. 3 Hypokalemia is possible late in the course of the toxicosis. Because of the high fat content of many chocolate products, pancreatitis is a potential sequela 24 to 72 hours after ingestion. Death is generally due to cardiac arrhythmias or respiratory failure.