Methyprylon ball-and-stick.png
Clinical data
Trade namesDimerin, Methyprylone, Noctan, Noludar
Routes of
By mouth
ATC code
Legal status
Legal status
Pharmacokinetic data
Protein binding60%
Elimination half-life6-16 hours
  • (RS)-3,3-diethyl-5-methylpiperidine-2,4-dione
CAS Number
PubChem CID
CompTox Dashboard (EPA)
ECHA InfoCard100.004.315 Edit this at Wikidata
Chemical and physical data
Molar mass183.251 g·mol−1
3D model (JSmol)
ChiralityRacemic mixture
  • CCC1(CC)C(=O)NCC(C)C1=O
  • InChI=1S/C10H17NO2/c1-4-10(5-2)8(12)7(3)6-11-9(10)13/h7H,4-6H2,1-3H3,(H,11,13) checkY
 ☒NcheckY (what is this?)  (verify)

Methyprylon[1], or Noludar, is a sedative of the piperidinedione derivative family first developed by Hoffmann-La Roche.[2] This medicine was used for treating insomnia, but is now rarely used as it has been replaced by newer drugs with fewer side effects, such as benzodiazepines.[3]

Methyprylon was withdrawn from the US market in June 1975 and the Canadian market in September 1990. Some other trade names are Noctan and Dimerin.

Adverse effects

Side effects can include skin rash, fever, depression, ulcers or sores in mouth or throat, unusual bleeding or bruising, confusion, fast heartbeat, respiratory depression, swelling of feet or lower legs, dizziness, drowsiness, headache, double vision, clumsiness, constipation, diarrhea, nausea, vomiting, unusual weakness.[citation needed]


A study of single oral doses of 300 mg in healthy volunteers found that the zero-order absorption model fit the data best. Mean (+/- SD) values for the half-life (9.2 +/- 2.2 h), apparent clearance, (11.91 +/- 4.42 mL/h/kg) and apparent steady-state volume of distribution, (0.97 +/- 0.33 L/kg) were found.[4]

A case report found that the pharmacokinetics of methyprylon were not concentration dependent in an overdose case; explanations included saturation or inhibition of metabolic pathways. The generally accepted half-life for a therapeutic dose was not found appropriate in intoxicated patients and would underestimate the time required to reach a safe concentration of the drug.[5]

See also


  1. ^ US Patent 2680116 Piperidones and Process for the Manufacture Therof
  2. ^ US granted 2680116, Frick H, Lutz AH, "Piperidiones and Process for the Manufacture thereof", issued 1954-06-01, assigned to Hoffmann-La Roche 
  3. ^ Lomen P, Linet OI (1976). "Hypnotic efficacy of triazolam and methyprylon ininsomniac in-patients". The Journal of International Medical Research. 4 (1): 55–8. doi:10.1177/030006057600400108. PMID 16792. S2CID 12500779.
  4. ^ Gwilt PR, Pankaskie MC, Thornburg JE, Zustiak R, Shoenthal DR (September 1985). "Pharmacokinetics of methyprylon following a single oral dose". Journal of Pharmaceutical Sciences. 74 (9): 1001–3. doi:10.1002/jps.2600740920. PMID 2866242.
  5. ^ Contos DA, Dixon KF, Guthrie RM, Gerber N, Mays DC (August 1991). "Nonlinear elimination of methyprylon (noludar) in an overdosed patient: correlation of clinical effects with plasma concentration". Journal of Pharmaceutical Sciences. 80 (8): 768–71. doi:10.1002/jps.2600800813. PMID 1686463.