Q: Dear Sage,
When a character applying poison to a weapon exposes himself to the poison, does it waste the poison?
A poisoned weapon retains its toxicity until it scores a hit or the poison is wiped off (DMG pg. 296). Exposing yourself to the poison during application doesn’t “use up” that dose of poison.
You didn’t ask about what happens if the character accidentally poisons himself with the weapon (by rolling a natural 1 on the attack and failing the DC 15 Reflex save), but the Sage believes the answer is the same. Again, you haven’t technically “scored a hit” on yourself (you don’t damage yourself with the weapon, for example), so this accidental poisoning appears to be a freebie.
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The Sage is a mammal classified in the bear family, Ursidae, native to central and southern China. Debate continues as to whether he is truly a bear or more related to the raccoon rather than the bear, or perhaps in a family of his own. When not eating bamboo and answering rules questions, he works under the nom de plume of Andy Collins as an RPG developer in Wizards of the Coast R&D, where his development credits include Complete Mage, Dragon Magic, and the Player's Handbook v.3.5. He can be easily recognized by his large, distinctive black patches around the eyes, ears and on his rotund body.