Pepper plants are in the Solanaceae plant family, which also includes violently poisonous nightshade and many other toxic species. Some pepper plants are poisonous to both humans and animals, even those peppers commonly used in food. Poisonous peppers may be growing in your garden or in your home right now.

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Some of the most common garden peppers are poisonous.

Hot Peppers

Hot peppers, Capsicum annuum, also called chili peppers, are toxic. Chili peppers are commonly used in the garden and the kitchen for their hot, spicy flavor. The hot flavor is actually a result of the mildly poisonous nature of the plant. The leaves and fruits of chili peppers are toxic when touched and eaten. The burning sensation you get when you handle or eat hot peppers is the toxicity of the plant. When large quantities of pepper are consumed, you will feel a burning of the throat, tongue, eyes and skin. Vomiting may also result when large amounts of chili peppers are consumed.

Ornamental Pepper Plant

The ornamental pepper plant, Solanum pseudocapsicum, may also be known by the deceptive names natal cherry, winter cherry and Jerusalem cherry. The names suggest that ornamental peppers are something that should be eaten, when in fact they are poisonous and dangerous to pets and wildlife. The plant is toxic to dogs, cats and horses. When ingested, ornamental pepper plants may cause gastrointestinal ulcers, seizures, respiratory problems and shock.

Poison Devil's Pepper

The poison devil's pepper, Rauvolfia vomitoria, resembles a tree. Growing taller than 30 feet, poison devil's pepper produces reddish-orange fruits, but every part of the tree is highly toxic. Even touching parts of poison devil's pepper may cause nausea. Poison devil's pepper is invasive, and will take over the habitats of other trees, driving out life in favor of its own survival.

Pepper Trees

Parts of the California pepper tree, Schinus molle, and the Brazilian pepper tree, Schinus terebinthisfolius, are poisonous when touched or ingested. Touching the fruits and foliage may result in skin irritation and inflammation in both humans and animals. The fruits are only mildly poisonous, inducing vomiting and diarrhea when eaten.