A character that is poisoned takes health damage per round. The amount of damage caused is usually reduced per round that damage is dealt.
Causes of Poison
Poison can be caused by a number of methods such as weapons specifically scripted to poison the target (there are several varieties of these), using a vial of poison to coat a mundane weapon causing poison flares, or it can be caused by a creature, such as a viper, using a natural attack. Some creatures will poison a character when that character attempts to skin that creatures. There are also poison needle traps, which can be extracted via Lock Mastery and set as traps in any container. Sea-green scarab traps will also poison the unperceptive, and unskilled foragers have a higher chance of being poisoned.
Creatures That Poison
Poison dissipates as it causes damage. For example, poison with a rate of dissipation of 5 per round that causes 60 damage per round will cause 60 damage in the first round, then 55, then 50, until the damage per round reaches 0 or less, in which the character will no longer suffer damage from the poison. Dissipation rates of 0 have been seen, which means the poison will continue to do damage until it is cured.
While poisoned, the HEALTH verb will display the following:
Needless to say, this character died the next round.
Cures of Poison
The spell, Unpoison (114), will instantly remove any poison, no matter how severe the poison is. However, a character that is inflicted with multiple poisons will need to have this spell cast upon them for each poison the character is suffering from.
Firethorns, the skin from a firethorn shoot, will cure poison when eaten. Also, a bite of ochre-colored fungus, which can be foraged for in one of Zul Logoth's tunnels (only in the rooms with the ochre-colored fungus) will cure poison when eaten.