Methamphetamine Amphetamines Psychostimulants

The best-known products come from the amphetamine group (see Table 1.12) Dexedrine1 1 (generic name d-amphetamine) and Pervitin 1 (methamphetamine) were particularly used in the 1950s and 1960s as stimulants and also as appetite suppressants, but today play hardly any role in medical practice. Ritalin (methylphenidate) has some relevance its psychostimulant action is said to be weaker than that of amphetamines and it is apparent ) less abused than the latter. Because methylphenidate also possesses mild antidepressant activity, in some countries it is used to combat not only narcolepsy and ADHD but also mild depressions without suicide risk (Satel and Nelson, 1989). 

Amphetamine and methamphetamine possess an essentially pure psychostimulant effect however, substituted derivatives in position 3 and 4 on benzene ring are defined as entactogene [14], This class of substances includes methylenedioxymethamphetamine (MDMA), methylenedioxyamphetamine (MDA), methylenedioxyethyl-amphetamine (MDEA), and others such as the /V-melhyl-l-(3-4-methylenedioxyphenyl)-2-butanamine (MBDB), methoxymethylenedioxyam-phetamine (MMDA) (Fig. 4). All of these substances are more active in the d form. There are also amphetamine-like substances which combine sympathomimetic (euphoric) and hallucinogen effects they are primary amines, trisubstituted on the benzene ring, that produce effects similar to mescaline. Among these the 2,5-dime-thoxy-4-methylamphetamine (DOM) is the most important. 

In conclusion, animal studies have shown that MPH has an abuse liability similar to that of other Schedule II stimulants, including amphetamine, methamphetamine, and cocaine. Actual data on abuse indicate that the pattern of MPH abuse is similar to that of other potent psychostimulants and that MPH is diverted and abused to a similar extent as other pharmaceutical Schedule II substances. Taken collectively, the data indicate that MPH fits the profile of a Schedule II substance. 

Mach et al. (1997) used PET in rhesus monkeys to confirm the similarity of effects among methylphenidate, amphetamine, methamphetamine, and cocaine on dopamine release in the basal ganglia. It is inevitable that methylphenidate will produce similar neurotoxic effects as other psychostimulants. 

The psychostimulant activity of selegiline was initially attributed to the two major metabolites of selegiline, L-amphetamine and L-methamphetamine . However, due to their low concentrations in the brain and the low activity of the L-isomers of methamphet-amine and amphetamine compared with the psychoactive D-enantiomers, it seems that their contribution cannot be significant. ... 

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