Single Isomer Medication 

Dennis B. Kottler, MD

Westlake Village, CA

Appointments:   818-991-8376 

Email:   doc@psychiatrix.com

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"Single isomer" medications often represent a modification of existing medication.  Many psychiatric medications exist in a "racemic" mix of molecules comprised of mirror-image isomers (enantiomers).   These mirror-image molecules bend light in opposite directions.  Hence one group is labeled dextro-rotary and the other group is labeled levo-rotary.

One of the  "single isomers" recently introduced is Nuvigil, a single isomer form of Provigil, a drug for various forms of daytime sleepiness

Lexapro, is a single isomer form of Celexa, an antidepressant medication.    A possible advantage of Lexapro is fewer side effects and greater effectiveness at a lower dose vs. the racemic Celexa.  

Recently Focalin (dexmethylphenidate) was introduced.  It is the single isomer form of Ritalin (methylphenidate).

Other single isomer medications will be introduced in the future, a movement encouraged by the FDA.

Unfortunately a single isomer form of Prozac (R-Fluoxetine) never made it through the FDA regulatory process.  Perhaps it will return.


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Appointments:   818-991-8376 

Email:   doc@psychiatrix.com