Flurazepam

Flurazepam

Clinical data
Trade names	Dalmane
AHFS/Drugs.com	Monograph
MedlinePlus	a682051
Pregnancy category	X (Contraindicated in pregnancy)
Routes of administration	Oral
ATC code	N05CD01 (WHO)
Legal status
Legal status	CA: Schedule IV DE: Anlage III (Prescription only) US: Schedule IV
Pharmacokinetic data
Bioavailability	83%
Metabolism	Hepatic
Biological half-life	40–250 hours
Excretion	Renal
Identifiers
IUPAC name 7-Chloro-1-[2-(diethylamino)ethyl]-5-(2-fluorophenyl)-1,3-dihydro-2H-1,4-benzodiazepin-2-one
CAS Number	17617-23-1 Y
PubChem (CID)	3393
IUPHAR/BPS	7188
DrugBank	DB00690 Y
ChemSpider	3276 Y
UNII	IHP475989U Y
KEGG	D00329 Y
ChEMBL	CHEMBL968 Y
PDB ligand ID	FL7 (PDBe, RCSB PDB)
ECHA InfoCard	100.037.795
Chemical and physical data
Formula	C21H23ClFN3O
Molar mass	387.88 g/mol
3D model (Jmol)	Interactive image
Melting point	79.5 °C (175.1 °F)
SMILES FC1=CC=CC=C1C2=NCC(N(CCN(CC)CC)C3=C2C=C(C=C3)Cl)=O
InChI InChI=1S/C21H23ClFN3O/c1-3-25(4-2)11-12-26-19-10-9-15(22)13-17(19)21(24-14-20(26)27)16-7-5-6-8-18(16)23/h5-10,13H,3-4,11-12,14H2,1-2H3 Y Key:SAADBVWGJQAEFS-UHFFFAOYSA-N Y

Flurazepam (marketed under the brand names Dalmane and Dalmadorm) is a drug which is a benzodiazepine derivative. It possesses anxiolytic, anticonvulsant, sedative and skeletal muscle relaxant properties. It produces a metabolite with a long half-life, which may stay in the bloodstream for days.

Flurazepam was initially patented in 1963 and went on sale in the United States in 1970.

Flurazepam is officially indicated for mild to moderate insomnia and as such it is used for short-term treatment of patients with mild to moderate insomnia such as difficulty falling asleep, frequent awakening, early awakenings or a combination of each. Flurazepam is a long-acting benzodiazepine and is sometimes used in patients who have difficulty in maintaining sleep. Flurazepam is still available in the United States. Intermediate half-life benzodiazepines are also useful for patients with difficulty in maintaining sleep (e.g. loprazolam, lormetazepam, temazepam).

The most common adverse effects are dizziness, drowsiness, light-headedness, and ataxia. Flurazepam has abuse potential and should never be used with alcoholic beverages or any other substance that can cause drowsiness. Addictive and possibly fatal results may occur. Flurazepam users should only take this drug strictly as prescribed, and should only be taken directly before the user plans on sleeping a full night. Next day drowsiness is common and may increase during the initial phase of treatment as accumulation occurs until steady-state plasma levels are attained.

A review paper found that long-term use of flurazepam is associated with drug tolerance, drug dependence, rebound insomnia and CNS related adverse effects. Flurazepam is best used for a short time period and at the lowest possible dose to avoid complications associated with long-term use. Non-pharmacological treatment options however, were found to have sustained improvements in sleep quality. Flurazepam and other benzodiazepines such as fosazepam, and nitrazepam lost some of their effect after seven days administration in psychogeriatric patients. Flurazepam shares cross tolerance with barbiturates and barbiturates can easily be substituted by flurazepam in those who are habituated to barbiturate sedative hypnotics.