General Description
Odorless creamy-white to pale-yellow powder or white crystalline solid. Bitter taste. pH (2% aqueous suspension) 4.8-7.
Reactivity Profile
OXAZEPAM(604-75-1) is stable in light and is non hygroscopic. OXAZEPAM(604-75-1) is stable in neutral solution. This chemical is hydrolyzed by acids and bases.
Air & Water Reactions
Insoluble in water.
Fire Hazard
Flash point data for this chemical are not available; however, OXAZEPAM is probably combustible.
Chemical Properties
Off-White Solid
Originator
Serax,Wyeth,US,1965
Uses
Anxiolytic; muscle relaxant (skeletal); anticonvulsant; ligand for the GABAA receptor benzodiazepine modulatory site. Controlled substance (depressant).
Definition
ChEBI: A 1,4-benzodiazepinone that is 1,3-dihydro-2H-1,4-benzodiazepin-2-one substituted by a chloro group at position 7, a hydroxy group at position 3 and phenyl group at position 5.
Manufacturing Process
(A) Suspend 10 g of 7-chloro-1,3-dihydro-5-phenyl-2H-1,4-benzodiazepin-2one 4-oxide in 150 ml of acetic anhydride and warm on a steam bath with stirring until all the solid has dissolved. Cool and filter off crystalline, analytically pure 3-acetoxy-7-chloro-1,3-dihydro-5-phenyl-2H-1,4benzodiazepin-2-one, melting point 242°C to 243°C.
(B) Add to a suspension of 3.4 g of 3-acetoxy-7-chloro-1,3-dihydro-5-phenyl2H-1,4-benzodiazepin-2-one in 80 ml of alcohol.6 ml of 4 N sodium hydroxide. Allow to stand after complete solution takes place to precipitate a solid. Redissolve the solid by the addition of 80 ml of water. Acidify the solution with acetic acid to give white crystals. Recrystallize from ethanol to obtain 7chloro-1,3-dihydro-3-hydroxy-5-phenyl-2H-1,4-benzodiazepin-2-one, melting point 203°C to 204°C.
Brand name
Serax (Alpharma); Zaxopam (Quantum Pharmics).
Therapeutic Function
Tranquilizer
Pharmacokinetics
The half-life of oxazepam is approximately 4 to 8 hours, and cumulative effects with chronic therapy
are much less than with long-acting benzodiazepines, such as chlordiazepoxide and diazepam. Lorazepam is the
2′-chloro derivative of oxazepam and has a similarly short half-life (2–6 hours) and pharmacological activity.
Drug interactions
Potentially hazardous interactions with other drugs
Antibacterials: metabolism possibly increased by
rifampicin.
Antipsychotics: enhanced sedative effects; risk of
serious adverse effects in combination with clozapine.
Antivirals: possibly increased concentration with
ritonavir.
Sodium oxybate: enhanced effects of sodium oxybate
- avoid.
Ulcer-healing drugs: metabolism inhibited by
cimetidine.
Metabolism
Oxazepam is an active metabolite of both chlordiazepoxide and diazepam and is marketed separately, as a shortacting anxiolytic agent. Oxazepam is rapidly inactivated to glucuronidated metabolites that are excreted in the urine.
