Poison - cosmetic damage

[Quasqueton]

This man was poisoned:

I've never thought of "cosmetic" damage from poison, but the concept could prove interesting for D&D poison.

Quasqueton

 

[Ogrork the Mighty]

In terms of cosmetic damage, I'd just apply a penalty to Charisma-related checks in which appearance plays a role. I would only reduce Charisma itself if the resulting cosmetic damage was enough to reduce the character's self-confidence and personality.