D,l-methylphenidate

Methylphenidate as a secondary amine gives rise to four optical isomers d-threo, 1-threo, d-erythro, and 1-erythro. There is stereoselectivity in receptor site binding and its relationship to response. The standard preparation is comprised of the threo recemate as it appears to be the CNS active form. Moreover, recent data suggests that the d-methylphenidate isomer is the active form. This has led to the development of a purified d, threo-methylphenidate compound, Focalin. Studies have shown Focalin to be at least as effective as the racemate at half the dosage. Focalin is available in 2.5, 5, and 10 mg to approximate 5, 10, and 20 mg of d,l methylphenidate. 

Unknown how d,l-amphetamine s mechanism of action differs from fhaf of d,l-methylphenidate, but some patients respond to or tolerate d,l-amphetamine better than d,l-methylphenidate and vice versa... 

Consider adjusting dose or switching to another formulation of d,l-methylphenidate or to another agent... 

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

CNS and cardiovascular actions of d,l-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, anti psych otics should inhibit the stimulatory effects of d,l-methylphenidate... 

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

Theoretically, d,l-methylphenidate could inhibit the mood stabilizing actions of atypical antipsychotics in some patients Combination of d,l-methylphenidate with mood stabilizers (lithium, anticonvulsants, atypical antipsychotics) is generally something for experts only, when monitoring patients closely and when other options fail... 

Emergence or worsening of activation and agitation may represent the induction of a bipolar state, 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,l-methylphenidate... 

Patients who are not taking racemic d,l-methylphenidate initial 2.5 mg twice per day in 4-hour intervals may adjust dose in weekly intervals by 2.5-5 mg/day maximum dose generally f 0 mg twice per day... 

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... 

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