Title: Butalbital
CAS Registry Number: 77-26-9
CAS Name: 5-(2-Methylpropyl)-5-(2-propenyl)-2,4,6(1H,3H,5H)-pyrimidinetrione
Additional Names: 5-allyl-5-isobutylbarbituric acid; 5-allyl-5-(2-methylpropyl)barbituric acid; 5-isobutyl-5-allylbarbituric acid; alisobumal; allylbarbital; itobarbital; tetrallobarbital
Trademarks: Sandoptal (Sandoz)
Molecular Formula: C11H16N2O3
Molecular Weight: 224.26
Percent Composition: C 58.91%, H 7.19%, N 12.49%, O 21.40%
Literature References: Prepn: Volwiler, J. Am. Chem. Soc. 47, 2236 (1925).
Properties: Prisms, mp 138-139°. Slightly bitter taste. Practically insol in water and petr ether. Sol in alcohol, chloroform, ether, acetone, glacial acetic acid, also in solns of fixed alkali hydroxides. A satd aq soln is acid to litmus.
Melting point: mp 138-139°
NOTE: This is a controlled substance (depressant): 21 CFR, 1308.13.
Therap-Cat: Sedative, hypnotic.
Keywords: Sedative/Hypnotic; Barbituric Acid Derivatives.
Butallylonal Butamben Butamirate Butamisole Butanilicaine

Butalbital structure.svg
Butalbital ball-and-stick.png
Systematic (IUPAC) name
Clinical data
AHFS/Drugs.com Micromedex Detailed Consumer Information
MedlinePlus a601009
Pregnancy cat. C (US)
Legal status Schedule III (US)
Routes oral
Pharmacokinetic data
Bioavailability 20-45%
Metabolism hepatic mainly CYP3A4
Half-life 35 hours [1]
Excretion renal
CAS number 77-26-9 YesY
ATC code None
PubChem CID 2481
DrugBank DB00241
ChemSpider 2387 YesY
KEGG D03182 YesY
ChEBI CHEBI:102524 YesY
Chemical data
Formula C11H16N2O3 
Mol. mass 224.256
 YesY (what is this?)  (verify)

Butalbital is a barbiturate with an intermediate duration of action. Butalbital is often combined with other medications, such as acetaminophen (paracetamol) or aspirin, and is commonly prescribed for the treatment of pain and headache. The various formulations combined with codeine are FDA approved for the treatment of tension headaches. Butalbital has the same chemical formula as talbutal but a different structure—one that presents as 5-allyl-5-isobutylbarbituric acid,[2]