The DMG provides detailed rules on poison types and effects. The following rules add several types of non-lethal poisons, introduce poison gases, and describe some poison antidotes.
Sedatives are ingested poisons that disable, rather than injure, a character. A sedative can be administered in food or drink, with different rates and effects:
| Method | Onset | Weakness | Duration |
|---|---|---|---|
| Eaten | 4-40 min. |
1-6 min. |
2-12 hours |
| Drunk | 2-12 min. |
1-6 min. |
1-4 hours |
Sedatives are treated as regular poisons, except that their first effect is a period of weakness when all ability scores and the character's movement rate are reduced to half. This lasts 1d6 rounds, after which the character saves vs. poison. Failure renders him unconscious. Success means that the weakness lasts for another hour. The character then saves each hour, with the weakness remaining until a successful save is made.
Poison Gases are rare, expensive, and highly dangerous. A typical dose is a clay or glass jar weighing 5 pounds. If the jar is shattered or opened, gas fills a 10' x 10' x 10' cube. It disperses after one round unless contained on all sides. The gas lasts for 2d6 turns in an enclosed room; 2d6 rounds in a room with at least one open door, window, arrow slit, etc.
It might be possible for creative players to create larger doses of poison gas, but such lethal devices are left to the DM's discretion.
Poison gases generally have the effects of poison type D, taking effect after one or two minutes, inflicting 30 points of damage (2d6 with a successful save). The damage is inflicted each turn the character breathes the gas.
An extremely lethal poison gas is reputed to exist, similar to poison type J (onset in 1d4 minutes, causes death or 20 points of damage with save).
Unlike injected or ingested poisons, however, poison gas does not remain in a character's system after death. Thus, attempts to raise characters who have perished this way do not have to contend with the venom in the character's system.
Poison Antidotes[]
(Optional Rule)
In AD&D® 2nd Edition rules, a character with healing proficiency is able to aid poisoned individuals. This is described in Chapter Five of the Player's Handbook. We reproduce those rules here with additional options, including ones for those campaigns that are not using nonweapon proficiency rules.
Campaigns without Nonweapon Proficiencies[]
Treat rangers, characters with forester secondary skills, and thieves with the kits assassin, bounty hunter, and scout as having herbalism proficiency; treat clerics and paladins as having healing proficiency; and treat druids as having both
Healing Proficiency and Poison[]
The basic healing proficiency rules for poison, from the Player's Handbook, are as follows.
A character with healing proficiency can attempt to aid a poisoned individual, provided the poison entered through a wound. If the poisoned character can be tended immediately (the round after the character is poisoned) and the care continues for the next five rounds, the victim gains a +2 to his saving throw (delay his saving throw until the last round of tending). No proficiency check is required, but the poisoned character must be tended to immediately (normally by sacrificing any other action by the proficient character) and cannot do anything himself. If the care and rest are interrupted, the poisoned character must immediately roll a normal saving throw for the poison. This result is unalterable by normal means (i.e., more healing doesn't help). Only characters with both healing and herbalism proficiencies can attempt the same treatment for poisons the victim has swallowed or touched (the character uses his healing to diagnose the poison and his herbalist knowledge to prepare a purgative.)
Note that these rules concern antidotes only obliquely, through the herbalism proficiency in instances of ingestive and contact poisoning.
Antidote Effects[]
Antidotes can be manufactured for most poisons. To use an antidote you must match it with its poison (see the assassin kit), or just administer an antidote and hope that by chance it is the right one. (The DM may permit the existence of some antidotes that counter more than one poison, e.g., both types A and B injected.) An antidote will take effect if administered immediately or at least before the toxin's onset time. It then either negates the poison entirely (if the poisoned character made his saving throw in the first place) or reduces its effect to saving throw level.
Producing Antidotes[]
Most of the time an antidote has not been prepared in advance, and a character with herbalism proficiency will attempt to produce an antidote from scratch.
Doing this presupposes an assortment of herbs, mosses, and such necessary materials, already selected and close at hand (e.g., gathered, dried and stored in a pouch). If the herbalist needs to gather the materials as well (and there are materials around to be gathered—not the case in most dungeons), at least half an hour is required to do so. When materials are available, putting together and administering an antidote takes 1d6+4 (5-10) minutes.
If time for gathering materials and making the antidote turns out to be greater than the poison's onset time, the efforts are in vain. If not, a proficiency check must be made to determine the antidote's success or failure. The check suffers a -10 penalty if the poison has not been identified. If the check is successful, the antidote takes effect.
For example, the assassin Therius is adventuring with his companion, Orlene, when she is struck by a poisoned blade. The opponent is swiftly dispatched and Therius turns his attention to her wound. Orlene, meanwhile, has failed her saving throw. The DM knows that the poison is Type O, injected, with an onset time of 20 minutes; he notes this information secretly. One minute has already gone to finishing combat. If the poison is not successfully treated, Orlene will be left paralyzed for nine hours.
Therius is a 7th level thief (assassin kit) with herbalism proficiency and Intelligence 14; he does have a kit of useful herbs with him just for such emergencies as this.
He first sets out to identify the poison. His base chance is 35% (7th level) + 5% (Int 14) = 40%. This is his chance of learning from Orlene's symptoms. He rolls a 48 on percentile dice and fails. His next attempt is by sight, examining the slain opponent's blade, with a 20% chance of success. This also fails. Concerned about time (three minutes have already ticked by), Therius puts a dab on his tongue. He needs to roll 35 or lower . . . and gets a 26! He spits out the poison, recognizing it as type O. The DM doesn't bother to see if the poison affects Therius, since a paralytic poison at half strength would have no effect.
Therius works to produce an antidote with the materials in his pouch. This takes him six minutes. He then makes a proficiency check, needing a 12 or lower (because herbalism has a -2 modifier—see Player's Handbook, Chapter Five) for success. He rolls a 13—failure! Nine minutes have ticked by. He hurriedly attempts again to concoct the antidote. This time it takes a full 10 minutes . . . Therius rolls a 9 this time, however, so he succeeds just in the nick of time.
The antidote totally halts the paralytic poison, since that is what the result of a successful saving throw would have been.