Haloxazolam structure.svg
Clinical data
Trade names Somelin (JP)
AHFS/Drugs.com International Drug Names
Routes of
ATC code
  • none
Legal status
Legal status
Pharmacokinetic data
Metabolism Hepatic
Excretion Renal
CAS Number
PubChem CID
Chemical and physical data
Formula C17H14BrFN2O2
Molar mass 377.208 g/mol g·mol−1
3D model (JSmol)
 ☒N☑Y (what is this?)

Haloxazolam (marketed in Japan under the brand name Somelin), is a drug which is a benzodiazepine derivative.[1][2][3] It has similar hypnotic properties as the benzodiazepine drugs triazolam, temazepam, and flunitrazepam and as such is indicated for the treatment insomnia.[4] A study in cats comparing estazolam and haloxazolam found that haloxazolam only affects gamma motor neurons, whereas estazolam affects both alpha and gamma motor neurons.[5]

See also[edit]


  1. ^ Tanaka, E; Terada, M; Misawa, S; Wakasugi, C (1996). “Simultaneous determination of twelve benzodiazepines in human serum using a new reversed-phase chromatographic column on a 2-microns porous microspherical silica gel”. Journal of Chromatography B. 682 (1): 173–8. doi:10.1016/0378-4347(96)00121-1. PMID 8832439.
  2. ^ “Benzodiazepine Names”. non-benzodiazepines.org.uk. Archived from the original on 2008-12-08. Retrieved 2009-04-05.
  3. ^ Guan, F; Seno, H; Ishii, A; Watanabe, K; Kumazawa, T; Hattori, H; Suzuki, O (1999). “Solid-phase microextraction and GC-ECD of benzophenones for detection of benzodiazepines in urine”. Journal of Analytical Toxicology. 23 (1): 54–61. doi:10.1093/jat/23.1.54. PMID 10022210.
  4. ^ Tan, X; Uchida, S; Matsuura, M; Nishihara, K; Kojima, T (2003). “Long-, intermediate- and short-acting benzodiazepine effects on human sleep EEG spectra”. Psychiatry and Clinical Neurosciences. 57 (1): 97–104. doi:10.1046/j.1440-1819.2003.01085.x. PMID 12519461.
  5. ^ Sakai, Y (1983). “Comparative study on the effects of haloxazolam and estazolam, new sleep inducing drugs, on the alpha- and gamma-motor systems”. Japanese Journal of Pharmacology. 33 (5): 1017–25. doi:10.1254/jjp.33.1017. PMID 6139494.