Clinical data
Trade namesNopron
Other namesCERM-1709
AHFS/Drugs.comInternational Drug Names
Routes of
ATC code
Legal status
Legal status
  • In general: ℞ (Prescription only)
Pharmacokinetic data
Elimination half-life~4.5 hours
  • N-{4-[4-(4-fluorophenyl)piperazin- 1-yl]butan- 2-yl}pyridine- 3-carboxamide
CAS Number
PubChem CID
ECHA InfoCard100.044.014 Edit this at Wikidata
Chemical and physical data
Molar mass356.445 g·mol−1
3D model (JSmol)
  • Fc3ccc(N2CCN(CCC(NC(=O)c1cccnc1)C)CC2)cc3
  • InChI=1S/C20H25FN4O/c1-16(23-20(26)17-3-2-9-22-15-17)8-10-24-11-13-25(14-12-24)19-6-4-18(21)5-7-19/h2-7,9,15-16H,8,10-14H2,1H3,(H,23,26)

Niaprazine (INN) (brand name Nopron) is a sedative-hypnotic drug of the phenylpiperazine group.[1][2] It has been used in the treatment of sleep disturbances since the early 1970s in several European countries including France, Italy, and Luxembourg.[3][4] It is commonly used with children and adolescents on account of its favorable safety and tolerability profile and lack of abuse potential.[5][6][7][8][9][10]

Originally believed to act as an antihistamine and anticholinergic,[11] niaprazine was later discovered to have low or no binding affinity for the H1 and mACh receptors (Ki = > 1 μM), and was instead found to act as a potent and selective 5-HT2A and α1-adrenergic receptor antagonist (Ki = 75 nM and 86 nM, respectively).[12] It possesses low or no affinity for the 5-HT1A, 5-HT2B, D2, and β-adrenergic, as well as at SERT and VMAT (Ki = all > 1 μM), but it does have some affinity for the α2-adrenergic receptor (Ki = 730 nM).[12]

Niaprazine has been shown to metabolize to the compound para-fluorophenylpiperazine (pFPP) in a similar manner to how trazodone and nefazodone metabolize to meta-chlorophenylpiperazine (mCPP).[13][14] It is unclear what role, if any, pFPP plays in the clinical effects of niaprazine.[12] However, from animal studies it is known that pFPP, unlike niaprazine, does not produce sedative effects, and instead exerts a behavioral profile indicative of serotonergic activation.[13]


  1. ^ Elks J (14 November 2014). The Dictionary of Drugs: Chemical Data: Chemical Data, Structures and Bibliographies. Springer. pp. 862–. ISBN 978-1-4757-2085-3.
  2. ^ Kent A, Billiard M (2003). Sleep: physiology, investigations, and medicine. New York: Kluwer Academic/Plenum. ISBN 978-0-306-47406-4.
  3. ^ Swiss Pharmaceutical Society (2000). Index Nominum 2000: International Drug Directory (Book with CD-ROM). Boca Raton: Medpharm Scientific Publishers. ISBN 978-3-88763-075-1.
  4. ^ Triggle DJ (1996). Dictionary of Pharmacological Agents. Boca Raton: Chapman & Hall/CRC. ISBN 978-0-412-46630-4.
  5. ^ Franzoni E, Masoni P, Mambelli M, Marzano P, Donati C (1987). "[Niaprazine in behavior disorders in children. Double-blind comparison with placebo]". La Pediatria Medica e Chirurgica: Medical and Surgical Pediatrics (in Italian). 9 (2): 185–7. PMID 2958783.
  6. ^ Bodiou C, Bavoux F (1988). "[Niaprazine and side effects in pediatrics. Cooperative evaluation of French centers of pharmacovigilance]". Thérapie (in French). 43 (4): 307–11. PMID 2903572.
  7. ^ Ottaviano S, Giannotti F, Cortesi F (October 1991). "The effect of niaprazine on some common sleep disorders in children. A double-blind clinical trial by means of continuous home-videorecorded sleep". Child's Nervous System. 7 (6): 332–5. doi:10.1007/bf00304832. PMID 1837245. S2CID 35908448.
  8. ^ Montanari G, Schiaulini P, Covre A, Steffan A, Furlanut M (1992). "Niaprazine vs chlordesmethyldiazepam in sleep disturbances in pediatric outpatients". Pharmacological Research. 25 (Suppl 1): 83–4. doi:10.1016/1043-6618(92)90551-l. PMID 1354861.
  9. ^ Younus M, Labellarte MJ (2002). "Insomnia in children: when are hypnotics indicated?". Paediatric Drugs. 4 (6): 391–403. doi:10.2165/00128072-200204060-00006. PMID 12038875. S2CID 33340367.
  10. ^ Mancini J, Thirion X, Masut A, et al. (July 2006). "Anxiolytics, hypnotics, and antidepressants dispensed to adolescents in a French region in 2002". Pharmacoepidemiology and Drug Safety. 15 (7): 494–503. doi:10.1002/pds.1258. PMID 16700077. S2CID 24273650.
  11. ^ Duchene-Marullaz P, Rispat G, Perriere JP, Hache J, Labrid C (1971). "[Some pharmacodynamical properties of niaprazine, a new antihistaminic agent]". Thérapie (in French). 26 (6): 1203–9. PMID 4401719.
  12. ^ a b c Scherman D, Hamon M, Gozlan H, et al. (1988). "Molecular pharmacology of niaprazine". Progress in Neuro-psychopharmacology & Biological Psychiatry. 12 (6): 989–1001. doi:10.1016/0278-5846(88)90093-0. PMID 2853885. S2CID 40566589.
  13. ^ a b Keane PE, Strolin Benedetti M, Dow J (February 1982). "The effect of niaprazine on the turnover of 5-hydroxytryptamine in the rat brain". Neuropharmacology. 21 (2): 163–9. doi:10.1016/0028-3908(82)90157-5. PMID 6460945. S2CID 22310059.
  14. ^ Garattini S, Mennini T (1988). "Critical notes on the specificity of drugs in the study of metabolism and functions of brain monoamines". International Review of Neurobiology. 29: 259–80. doi:10.1016/s0074-7742(08)60089-6. ISBN 9780123668295. PMID 3042665.