Butabarbital (trade name Butisol) is a prescription barbiturate sleep aid. Butabarbital has a particularly fast onset of effects and short duration of action compared to other barbiturates, which makes it useful for certain applications such as treating severe insomnia and relieving anxiety before surgical procedures; however it is also relatively dangerous particularly when combined with alcohol, and so is now rarely used, although it is still prescribed in some Eastern European and South American countries. Its intermediate duration of action gives butabarbital an abuse potential slightly lower than secobarbital.