1. Dear Drugs-Forum readers: We are a small non-profit that runs one of the most read drug information & addiction help websites in the world. We serve over 4 million readers per month, and have costs like all popular websites: servers, hosting, licenses and software. To protect our independence we do not run ads. We take no government funds. We run on donations which average $25. If everyone reading this would donate $5 then this fund raiser would be done in an hour. If Drugs-Forum is useful to you, take one minute to keep it online another year by donating whatever you can today. Donations are currently not sufficient to pay our bills and keep the site up. Your help is most welcome. Thank you.
    PLEASE HELP

Discriminative-Stimulus and Subject-Rated Effects of Methamphetamine, d-Amphetamine, Methylphenidate

Discriminative-Stimulus and Subject-Rated Effects of Methamphetamine, d-Amphetamine, Methylphenidate

  1. Jatelka
    Journal of Pharmacology and Experimental Therapeutics 2008 Dec 22. [Epub ahead of print]

    Sevak RJ (http://www.ncbi.nlm.nih.gov/sites/e...l.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlus), Stoops WW (http://www.ncbi.nlm.nih.gov/sites/e...l.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlus), Hays LR (http://www.ncbi.nlm.nih.gov/sites/e...l.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlus), Rush CR (http://www.ncbi.nlm.nih.gov/sites/e...l.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlus).

    Methamphetamine abuse is a significant public-health concern. Although widely studied in laboratory animals, little is known about the abuse-related behavioral effects of methamphetamine relative to other abused stimulants in controlled-laboratory settings in humans. The aim of this study was to examine the discriminative-stimulus, subject-rated, performance and cardiovascular effects of methamphetamine in humans. In the present study, subjects first learned to discriminate 10 mg oral methamphetamine from placebo. After acquiring the discrimination (>/= 80% drug-appropriate responding on four consecutive sessions), a range of oral doses of methamphetamine (2.5-15 mg), d-amphetamine (2.5-15 mg), methylphenidate (5-30 mg) and triazolam (0.0625-0.375 mg) were tested. Methamphetamine functioned as a discriminative-stimulus and produced prototypical stimulant-like subject-rated effects. d-Amphetamine and methylphenidate produced dose-related increases in methamphetamine-appropriate responding, whereas triazolam did not. d-Amphetamine and methylphenidate produced stimulant-like behavioral effects, while triazolam produced sedative-like effects. Methamphetamine, but no other drug, increased heart rate, systolic pressure and diastolic pressure significantly above placebo levels. Performance in the Digit-Symbol Substitution Test was not affected by any of the drugs tested. Overall, these results demonstrate that the acute behavioral effects of methamphetamine, d-amphetamine and methylphenidate overlap extensively in humans, which is concordant with findings from preclinical studies. Future studies should assess whether the similarity in the behavioral effects of methamphetamine and related stimulants can be extended to other behavioral assays, such as measures of reinforcement, in humans.