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Medications for Motor Symptoms

Osmolex ER (amantadine extended release)


Osmolex ER, an extended-release formulation of amantadine immediate release, was approved in 2018 by the U.S. Food and Drug Administration (FDA) to treat Parkinson's motor symptoms (tremor, slowness and stiffness). It works on the dopamine and glutamate brain chemical systems. Osmolex ER is taken once a day, in the morning.


In early Parkinson's or with mild symptoms, Osmolex ER may be an option to lessen motor symptoms. The once-a-day dosing may be beneficial for some.

Cons and Complications

The most common potential side effects include insomnia, nausea, dizziness and purple-red blotchy spots on the skin. In people with kidney problems, the dose may need to be decreased.

The medical information contained in this article is for general information purposes only. The Michael J. Fox Foundation for Parkinson's Research has a policy of refraining from advocating, endorsing or promoting any drug therapy, course of treatment, or specific company or institution. It is crucial that care and treatment decisions related to Parkinson's disease and any other medical condition be made in consultation with a physician or other qualified medical professional.

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