This extract causes you to take on a pale, sickly pallor for 1 round. During this time, if you consume a potion, it has no effect. Instead, your mouth fills with a vile poison that you can spit onto a weapon as a free action. If you do not spit out the poison in 1 round, it affects you instead. The effect of the poison depends on the level of spell contained in the potion consumed (see below). If the poison is not used within 1 minute per caster level it becomes inert. You can only create one dose of poison in this way per casting of this spell.