D-methylphenidate

Methylphenidate possesses two asymmetric carbon moieties, giving rise to four optical isomers d-threo, /-threo, d-erythro, and /-erythro (Patrick et ah, 1987). There is stereoselectivity in receptor site binding and its relationship to response. The standard preparation is comprised of the threo racemate as it appears to be the central nervous system (CNS) active form (Patrick et ah, 1987 Hubbard et ah, 1989). In addition, in rats, the d-methylphenidate isomer shows greater reuptake inhibition of DA and NE than the /-isomer (Patrick et ah, 1987). D-Methylphenidate is now available under the brand name Focalin. 

Methylphenidate (Ritalin, Methylin, (Metadate) (Concerta) (Ritalin LA) d-Methylphenidate (Focalin)... 

For the expert, can combine immediate release formulation of d-methylphenidate with a sustained release formulation of d,l-methylphenidate for ADHD... 

Although d-methylphenidate is generally considered to be twice as potent as racemic d,l-methylphenidate, some studies suggest that the d-isomer is actually more than twice as effective as racemic d,l-methylphenidate... 

CNS and cardiovascular actions of d-methylphenidate could theoretically be enhanced by combination with agents that block norepinephrine reuptake, such as the tricyclic antidepressants desipramine or protriptyline, venlafaxine, duloxetine, atomoxetine, milnacipran, and reboxetine... 

Theoretically, antipsychotics should inhibit the stimulatory effects of d-methylphenidate... 

Theoretically, d-methylphenidate could inhibit the antipsychotic actions of anfipsychofics... 

Emergence or worsening of activation and agitation may represent the induction of a bipolar sfafe, especially a mixed dysphoric bipolar II condition sometimes associated with suicidal ideation, and require the addition of a mood stabilizer and/or discontinuation of d-methylphenidate... 

Dexmethylphenidate—Novartis/Celgene. Focalin, D-MPH, D-methylphenidate hydrochloride, D-methylphenidate, dexmethylphenidate, dexmethylphenidate hydrochloride. Drugs R D. 2002 3(4) 279-82. 

Methylphenidate is indicated for the treatment of children with ADHD (5 to 10 mg p.o. daily) and for adults with narcolepsy (10 mg p.o. t.i.d.). Methylphenidate, a CNS stimulant and an analeptic, releases norepinephrine and hence stimulates the reticular activating system and the cerebral cortex. Its actions resemble those produced by amphetamine. Similar to other sympathomimetic agents, methylphenidate should be used with caution in patients with symptomatic cardiovascular disease, hyperthyroidism, angina pectoris, moderate to severe hypertension, or advanced arteriosclerosis because it may cause dangerous arrhythmias and blood pressure changes. 

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