Generally, dogs and cats don't have very good sense when it comes to what they eat. Many items, which are perfectly safe for the rest of the family, may cause problems with the family pets.

Chocolate - Chocolate contains two chemicals which are toxic to dogs. Theobromine, a naturally occurring chemical in the cocoa bean can cause vomiting, restlessness and muscle tremors. In high doses it may cause seizures, coma and even death. Chocolate also contains high levels of caffeine which can cause similar problems. Severity of the poisoning depends on the type of chocolate, size of the animal and amount of chocolate ingested. A veterinarian should be contacted immediately to weigh these risks. More detailed information on Chocolate Toxicosis can be found here.

Medication - Dogs and cats have much different body chemistries than people and medication will affect them differently from humans. If your dog or cat ingests any amount of medication not specifically prescribed for them, contact a veterinarian.

Plants - Many plants, indoor and outdoor, contain chemicals which may be harmful to pets. If you notice your pet ingesting plants or parts of plants, including seeds, flowers, or leaves, immediately stop them and try to identify what type of plant it is. Lists of poisonous plants may be found at the University of Pennsylvania and the University of Illinois websites. If you are unable to find the plant or find that it is toxic, contact a veterinarian.

Poison - Pets who regularly venture outside may come in contact with poisons meant for pests or vermin. Rat poison is the most common type of ingested poison. Rat poison works by inhibiting clotting of the blood. Size of the animal, and the amount and type of poison all play a part in how bad the toxicity is. Ant poison will rarely cause issues with pets due to their size, but many are encased in plastic containers which may have been shattered and ingested. A veterinarian should always be contacted if you believe that your pet ingested any type of poison. More detailed information on Rodenticide Toxicity can be found here.

Antifreeze - A common toxin seen in veterinary practices is antifreeze due to its sweet taste and common appearance in garages. The toxic ingredient is ethylene glycol, which attacks the liver and kidneys. There is a test for ethylene glycol, but it must be done quickly after ingestion. If you believe your pet has ingested antifreeze, consult a veterinarian immediately. More detailed information on Antifreeze Poisoning can be found here.