Eating chocolate can be very dangerous to cats. It can cause damage to the heart and brain, possibly even death. If your cat ingests chocolate, speak to a vet immediately for further advice.
Cats are much less likely to be interested in chocolate than dogs, but the risk of intoxication is thought to be the same or worse. Because of the small body size of the average cat, the amount needed to cause serious problems is quite small, especially with things like cocoa powder or baking chocolate. If you suspect your cat has ingested chocolate products, try to stay calm and speak to a vet as soon as possible. It can be very helpful if you have any package information at hand.
What is chocolate intoxication in cats? >What is chocolate intoxication in cats? [OverviewSymptoms of chocolate intoxication in cats >Symptoms of chocolate intoxication in cats [SymptomsCats at higher risk for chocolate intoxication >Cats at higher risk for chocolate intoxication [RisksDiagnosis of chocolate intoxication in cats >Diagnosis of chocolate intoxication in cats [DiagnosisVeterinary treatment of chocolate intoxication >Veterinary treatment of chocolate intoxication [Vet treatmentHome treatment of chocolate toxicity in cats >Home treatment of chocolate toxicity in cats [Home treatmentPrevention of chocolate intoxication >Prevention of chocolate intoxication [PreventionWhen to worry about Chocolate Intoxication >When to worry about Chocolate Intoxication [When to worry