Poison Spell
D&D Description of the Poison Spell : Calling upon the venomous powers of natural predators, you infect the subject with a horrible poison by making a successful melee touch attack. The poison deals 1d10 points of temporary Constitution damage immediately and another 1d10 points of temporary Constitution damage 1 minute later. Each instance of damage can be negated by a Fortitude save (DC 10 + 1/2 your caster level + your Wis modifier).
Deeper info on this Dungeons & Dragons Poison Spell