Products
In many countries, drugs containing butalbital are no longer approved (e.g., Cafergot-PB). Combination products are still on the market in some countries, including the United States, where numerous products are available.
Structure and properties
Butalbital (C11H16N2O3, Mr = 224.3 g/mol) or 5-allyl-5-isobutylbarbituric acid exists as a slightly bitter, white, odorless, crystalline powder that is soluble in boiling water.
Effects
Butalbital (ATC N05CA) has depressant, sedative, and sleep-inducing properties. The effects are due to interaction with GABA receptors, resulting in increased chloride transport and hyperpolarization of the cell membrane. Butalbital has a long half-life of 35 to 88 hours.
Indications
Butalbital is administered in combination with other agents (eg, acetylsalicylic acid, caffeine, acetaminophen, codeine) for the treatment of headache and migraine.