Dextroamphetamine

The prototype, amphetamine (52), is obtained by reductive amination of phenylacetone by means of ammonia and hydrogen. Isolation of the (+) isomer by resolution gives dextroamphetamine, a somewhat more potent stimulant than the racemate. 

The amphetamines, such as amphetamine, dextroamphetamine (Dexedrine), and metliainphetainine (Desoxyn), are sympatiiomimetic (ie, adrenergic) dru that stimulate the CNS (see Chap. 22). Their drug action results in an elevation of blood pressure, wakefulness, and an increase or decrease in pulse rate The ability of these drugs to act as anorexiants and suppress the appetite is thought to be due to their action on the appetite center in the hypothalamus. 

When a CNS stimulant such as dextroamphetamine is administered to treat a child with ADD, the drug regimen will be periodically interrupted to determine if the child still exhibits the symptoms of ADD. 

GrabowskiJ, RhoadesH, SchmitzJ,eral Dextroamphetamine for cocaine-dependence treatmenr a double-blind randomized clinical rrial. J Clin Psychopharmacol 21 522-526, 2001... 

Kornetsky C Hyporesponsivity of chronic schizophrenic patients to dextroamphetamine. Arch Gen Psychiatry 33 1425—1428, 1976 Kosten TR Pharmacotherapy of cerebral ischemia in cocaine dependence. Drug Alcohol Depend 49 133-144, 1998... 

Arnold, L.E. Kirilcuk, V. Corson, S.A. and Corson, E.O. Levoampheta-mine and dextroamphetamine Differential effect on aggression and hyperkinesis in children and dogs. Am J Psychiatry 130 165-170, 1973. Bain, G.T., and Kometsky, C. Naloxone attenuation of the effect of cocaine on rewarding brain stimulation. Life Sci 40 1119-1125, 1987. 

Winsberg, B.G. Press, M. Bialer, I. and Kupietz, S. Dextroamphetamine and methylphenidate in the treatment of hyperactive/aggressive children. Pediatrics 53 236-241, 1974. 

The relationship between dose and SLA was characterized by an inverted U-shaped curve for the phencyclinoids tested and dextroamphetamine. Geometric increases in cumulative IV doses produced nearly linear increases followed by decreases in SLA for each... 

FIGURE 5. Dose-response curves for the rate-increasing effects of phencyclinoids and dextroamphetamine on spontaneous locomotor activity. 

The proposed mechanism of ADHD pharmacotherapy is to modulate neurotransmitters in order to improve academic and social functioning. Pharmacologic therapy can be divided into two categories stimulants and non-stimulants. Stimulant medications include methylphenidate, dexmethylphenidate, amphetamine salts, and dextroamphetamine, whereas non-stimulant medications include atomoxetine, tricyclic antidepressants (e.g., imipramine), clonidine, guanfacine, and bupropion. 

Psychostimulants (e.g., methylphenidate and dextroamphetamine with or without amphetamine) are the most effective agents in treating ADHD. Once the diagnosis of ADHD has been made, a stimulant medication should be used first line in treating ADHD (Fig. 39-1). Stimulants are safe and effective, with a response rate of 70% to 90% in patients with ADHD.3,13,14 Generally, a trial of at least 3 months on a stimulant is appropriate, and this includes dose titration to response... 

Initial response to short-acting stimulant formulations (e.g., methylphenidate and dextroamphetamine) is seen within 30 minutes and can last for 4 to 6 hours.13,14 This short duration of effect frequently requires that short-acting stimulant formulations be dosed at least twice daily, thus increasing the chance of missed doses and non-compliance. Further, patients using any stimulant formulation but especially shortacting formulations can experience a rebound effect of ADHD symptoms as the stimulant wears off.14... 

Dextroamphetamine (Dexedrine) Intermedia te- acting 2.5-5 mg every morning T 2.5-5 mg/day in weekly intervals 5-20 mg twice daily (40 mg/day)... 

Dextroamphetamine/ 5-10 mg every morning T 5-10 mg/day in weekly 10-30 mg every morning or... 

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