I've already talked about diseases and parasites and curses so it's time for a bit on poisons.
There are many kinds of poison, differentiated by effect and method of delivery. They can be injected (needles, darts and other weapons), ingested or inhaled (there's a reason for poison tasters after all), or absorbed by touch (especially nasty for the treasure hungry). Depending on their toxicity they can be annoying, debilitating or painful. Some are faster to act, while others take days or weeks of accumulation to show their effects. Below are a few samples. Throughout these descriptions I've used the term resist to indicate a resistance check versus the potency of the poison described. Use whatever method suits your game system.
Laris - A contact poison distilled from the seeds of a tropical vine. Laris is a sticky white liquid that dries to a shiny film when exposed to air for any significant length of time. When it comes in contact with skin the film dissolves and enters the bloodstream, causing immediate paralysis (Great resist). Effects can last 3-6 days depending on the dose received. Washing a poisoned object with a mild acid (vinegar will do), destroys the poison. Wearing gloves eliminates the threat of contact. Because it is non-lethal, long lasting, and easily removed, Laris is commonly used to protect chests, vaults and strongboxes.
Matunus - A rare ingested poison made from the fleshy caps of a common temperate mushroom combined with the mild venom of a rare snake. Matunus is a dark red powder with a faint bitter taste. A single dose has no effect, but regular ingestion causes toxins to build up in the victim's system. Each day the poison is ingested requires a resist check, beginning at Poor and increasing one rank per week so long as the poison is included in the victim's diet. Once the victim succumbs they begin to suffer from general physical weakness and dizziness, suffering a Fair penalty to all actions. This penalty increases by one rank for each week the poisoning continues. If the poison is removed from the victim's diet the penalty is reduced one rank per month as the poison slowly leeches from their system.
Cyna - A dangerous injected poison harvested from the berries of an evergreen shrub found in cold climates. Cyna is a gelatinous green liquid with a with a sharp odor. When injected into the bloodstream it immediately affects the victim's nervous system, causing uncontrollable convulsion for 1d4 rounds (Great resist). The victim will be disoriented and confused for 1d4 rounds after the convulsions end. Convulsions reoccur every 30 to 40 minutes for six to eight hours after initial exposure. There are stories that certain native tribes use Cyna mixed with a sacred herbal compound as a hallucinogen.
Urtiva - A common injected and ingested poison made from easily available plants (though the proper recipe is difficult to follow). Urtiva is a thin yellow liquid with no taste or smell. It is often called Blackout, as its primary effects when injected or ingested is to cause unconsciousness, memory loss, and temporary blindness. Victims must resist (Great) to avoid the first two effects and make a second resist (Superb) to avoid the third. Memory loss is permanent and begins two to three hours before exposure and lasts until consciousness is regained. Blindness lasts eight to ten hours after exposure. The victim will remain unconscious for two to four hours. Urtiva is often used by thieves or muggers to neutralize their victims and remove any chance they will identify their assailants.
Hambrani - An uncommon contact and inhalation poison made from the distilled pollen of a rare cold climate flower. Hambrani is a black powder or solid at cooler temperatures, but vaporizes when warmed above 80 degrees (F). Even a tiny amount will create a poison cloud 10' in diameter. Direct contact with the powder or inhaling the vapor requires an immediate resist (Superb) or begin suffering searing pains beginning at the point of contact and quickly spreading to the victim's entire body. The victim suffers Good damage each round they are exposed to the poison plus four rounds. The Hambrani "poison bomb" consists of a solid piece of the poison molded into a ball of clay. When tossed into a fire or other heat source, the expanding Hambrani splits the clay shell and poisons anyone nearby.