Blood Level Profile in Man following Chronic Oral Administration of Flurazepam Hydrochloride

doi:10.1002/jps.2600621205

Journal of Pharmaceutical Sciences

Volume 62, Issue 12, December 1973, Pages 1932-1935

https://doi.org/10.1002/jps.2600621205 Get rights and content

Abstract

The blood level profile of flurazepam and its major metabolites was determined in man following the oral administration of 30 mg. daily for 2 weeks. The levels of the intact drug were below the sensitivity limit of the assay (< 3–4 ng./ml.). The hydroxyethyl metabolite was measurable only during the early hours after a 30-mg. oral dose and was not detectable after 24 hr. The major metabolite in blood was N-desalkyl-flurazepam, which reached steady-state (plateau) levels after 7 days. The half-life of elimination of the N-desalkyl metabolite ranged from 47 to 100 hr. No measurable amounts of the N-desalkyl-3-hydroxy metabolite were seen in blood.

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Research ArticlesBlood Level Profile in Man following Chronic Oral Administration of Flurazepam Hydrochloride

Abstract

J. Pharm. Sci.

J. Pharm. Sci.

J. Med. Chem.

Research Articles
Blood Level Profile in Man following Chronic Oral Administration of Flurazepam Hydrochloride