Central nervous system stimulants methylphenidate RITALIN

Central nervous system stimulants, e.g., amphetamine, methylphenidate (Ritalin) and cocaine... 

In 2005, a study appeared in Cancer Letters that would have evoked widespread media coverage if it had been about an illegal drug, rather than about a pharmaceutical company product (El-Zein, 2005). Researchers from the University of Texas examined 12 children treated with therapeutic effects of Ritalin to determine whether this central nervous system stimulant produces cytogenetic abnormalities in pediatric patients at therapeutic doses. Using peripheral blood lymphocytes taken from the children, they found a 2.4-fold increase in chromosome aberrations and similar defects. They concluded, These findings warrant further investigations of the possible health effects of methylphenidate in humans, especially in view of the well-documented relationship between elevated frequencies of chromosome aberrations and increased cancer risk. ... 

Central Nervous System Stimulants Central nervous system stimulants include agents such as the amphetamines (Dexedrine) and methylphenidate hydrochloride (Ritalin), used to elevate mood, suppress appetite, and control hyperkinetic disorders in children. Other examples include the illegal drugs methamphet-amine and cocaine. The mechanism of action of these drugs is to augment actions of the adrenergic nervous system. 

Methylphenidate (MPH, Ritalin ) is a central nervous system stimulant that is used for the treatment of attention deficit disorders, with and without hyperactivity, and narcolepsy. MPH has two chiral centres and is marketed as a racemic mixture. It is known that d-threo-MP is pharmacologically more active than l-threo-MPH. The drag is rapidly metabohzed in humans to the inactive ritalinic acid. High-throughput analysis with chiral selectivity is demanded for the bioanalysis of MPH and its major metabolite. 

The most commonly abused prescription drugs are opioids and opiates such as oxycodone and morphine, central nervous system depressants such as barbiturates and benzodiazepines, and stimulants such as dextroamphetamine and methylphenidate. Brand-name painkillers such as Vicodin and OxyContin, depressants such as Valium and Xanax, and stimulants such as Ritalin and Dexedrine are commonly abused (as are some OTC cough remedies). Although helpful and safe when used appropriately, these drugs can cause serious harm when taken in unapproved ways. 

Many drugs used for recreational as well as medical purposes can stimulate the central nervous system and so are referred to as stimulants. We separate. stimulants into tsvo groups according to their legal and social status. Controlled stimulants such as cocaine, amphetamines, methylphenidate (Ritalin), and related compounds are treated in this chapter, and over-the-counter stimulants such as nicotine and caffeine are dealt with in Chapters 7 and 8. We first consider the hi.story of stimulant use and discuss some of the effects of cocaine and the amphetamines as we review their history. Then we turn to a more detailed treatment of the pharmacology of these stimulants. 

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