HDMP-28 or methylnaphthidate is a stimulant drug of the piperidine and naphthylaminopropane groups, closely related to methylphenidate (Ritalin), but with the benzene ring replaced by naphthalene. It is a potent dopamine reuptake inhibitor, with several times the potency of methylphenidate and a short duration of action, and is a structural isomer of another potent dopamine reuptake inhibitor, N,O-Dimethyl-4-(2-naphthyl)piperidine-3-carboxylate. It has been sold as a designer drug since around 2015.

HDMP-28 and CFT overlay

Most of the TMP analogs of HDMP-28 have SERT Ki values in the range >10,000 and so are selective for dopamine and noradrenaline reuptake, with little or no effect on serotonin. HDMP-28 has high affinity to SERT, and so behaves as a triple reuptake inhibitor.

aEffect of (dl-threo) TMP and analogs on DA and 5-HT Transporters.
Ar[3H]CFT DAT[3H]DA Uptake[3H]RTI-55 SERTInhibition by 10μMD.R.Potency
Inhibition of specific analogs at displacing CFT from binding to DAT & RTI-55 from binding to SERT
Ph83.9224≫10,00019.62.71.00
p-F35.0142>10,00036.94.13.33
m-Cl5.123.0>10,00045.54.52.42
p-Me33.0126>10,00045.03.80.74
p-NH234.5114≫10,0007.93.32.18
m,p-Cl25.3 (2.67)b7.01,064 (>10,000)b93.31.37.98
β-Naphthyl33.9b 11.0c53.0c71.6bND4.8c
Cocaine160404401nd2.50.41
aSchweri, et al. (2002); bDavies, et al. (2004); cDeutsch, et al. (2001).

D.R. is the discrimination ratio = [3H]DA÷[3H]CFT.

A low D.R. indicates more addictive, whereas a high D.R. indicates low propensity for self-administration.

Legality

HDMP-28 is illegal in Switzerland as of December 2015.

See also

Further reading

  • Muhammed Ajeebsanu M, Subhahar MB, Karakka Kal AK, Philip M, Perwad Z, Karatt TK, etal. (January 2024). "Comprehensive metabolic investigation of dopamine reuptake inhibitor HDMP-28 in equine liver microsomes and Cunninghamella elegans for doping control". Drug Testing and Analysis. 16 (10): 1182–1194. doi:. PMID.