Poisonedit
From Memory Alpha, the free Star Trek reference
Poisons were toxicological substances that adversely affected living tissue, with effects ranging from slight discomfort to death. They could be natural or synthetic in origin. Poison secreted by animals was called venom. Nerve gases were synthetic poisons.
The venom of the mugato and the alkaloids of the Borgia plant were examples of natural poisons. Both were capable of killing an adult humanoid. (TOS: "A Private Little War", "The Man Trap") Artificial poisons included Felodesine chips and Veridium Six. (TNG: "The Defector", "Reunion")
On Dimorus, the indigenous rodent creatures used deadly poisoned darts as weapons. (TOS: "Where No Man Has Gone Before")
Sevrin died when he ate a poisonous fruit on Eden. (TOS: "The Way to Eden")
On Ligon II, the dueling weapons were coated with an alkaloid-based poison. As a result, a person could be killed instantaneously by a grazing wound. (TNG: "Code of Honor")
Commander Benjamin Sisko was skeptical about the orange bubbling liquid he was offered while in the third shap of the Wadi game Chula and thought that it could be a drug or poison, but ultimately it was the antidote for the gas. (DS9: "Move Along Home")
The Kaylo apple, found on a planet in the Delta Quadrant, was extremely poisonous and could lead to death. (VOY: "State of Flux")
Poisons were the favored method of assassination of the Flaxian Retaya. (DS9: "Improbable Cause")
The Vorta were genetically engineered to be immune to most types of poison. In 2373, Weyoun drank a glass of kanar containing enough voraxna poison to kill a dozen Cardassians. Afterward, he remarked that their physiology "comes in handy when you're a diplomat". (DS9: "Ties of Blood and Water")
