I thought for a while that poisons were relegated to melee weapons because of the whole "must break the skin to deliver the poison" bit, but bullets also apply poisons. There are also IRL cases of contact poisons, such as those used by North Korean and Russian spies, that would fit thematically.NWN Wikia wrote:Player characters may use these items on slashing or piercing weapons (or bullets) in an attempt to coat the weapon with the toxin, resulting in a temporary on-hit poison property.
Please allow poisons to be applied to all weapons, including bludgeoning ones.