OSMOLEX ER is a once-daily prescription medication used to treat adults with Parkinson’s disease and drug-induced extrapyramidal reactions.1

Person icon

What is Parkinson’s disease (PD)?2

  • PD is the second most common neurodegenerative disorder after Alzheimer’s disease
  • Symptoms include tremor or shaking, rigidity or stiffness, extreme slowness of intentional movement, and impaired balance
  • Onset of PD usually occurs after age 60
Extrapyramidal reaction icon

What are drug-induced extrapyramidal
reactions (EPR)?3,4

  • Drug-induced EPR are typically reversible effects to the nerves associated with motor activity
  • They occur after the administration of certain medications such as antipsychotics
  • Symptoms can begin immediately after administration or be delayed by hours or days
  • Are rarely life-threatening, but can cause distress for patients and their families
Unique delivery system icon

How does OSMOLEX ER work?

OSMOLEX ER contains amantadine, which is used in PD to help tremor.5
Extended-release icon
OSMOLEX ER is an extended-release amantadine tablet that utilizes a unique delivery system.1*

This unique delivery system involves an immediate-release outer layer of amantadine that dissolves 30 to 60 minutes after the pill is swallowed. The tablet shell then absorbs water, which pushes more amantadine out of the tablet through a laser-drilled hole at a steady rate.

This results in a consistent dose of amantadine.1,6

The Osmodex
delivery system

This delivery system allows for once-daily dosing with OSMOLEX ER. When taken in the morning, amantadine plasma
levels are higher during the day, without the need for a second mid-day dose.6

Osmotic pressure delivers amantadine at a controlled release rate throughout the day

Image labeling the drug delivery of an OSMOLEX® ER (amantadine) extended-release tablet Image labeling the drug delivery of an OSMOLEX® ER (amantadine) extended-release tablet
  • Image showing that the color coating and outer layer of amantadine dissolves
    The color coating and outer layer of
    amantadine dissolve
  • Image showing that the tablet shell is semipermeable, which lets water in without letting amantadine out
    The semipermiable tablet shell allows
    water in without letting amantadine out
  • Image showing how amantadine is released through the laser-drilled hole
    Amantadine release through the laser-drilled
    hole is driven by the osmotic pressure
*The biologically inert components of the tablet remain intact during gastrointestinal transit and are eliminated
in the stool as a tablet shell.


  1. OSMOLEX ER. Prescribing information. Adamas Pharmaceutical, Inc. 2021.
  2. Parkinson’s Disease. MassGeneral Institute for Neurodegenerative Disease. http://mghmind.org/disease-research/parkinsons-disease. Accessed April 18, 2019.
  3. Extrapyramidal Symptoms – statPearls.
  4. Blanchet P, Kivenko V. Drug-induced parkinsonism: diagnosis and management. Journal of Parkinsonism and Restless Legs Syndrome. 2016;6:83-91.
  5. Parkinson’s foundation. Amantadine. https://www.parkinson.org/Understanding-Parkinsons/Treatment/Prescription-Medications/Amantadine-Symmetrel. Accessed November 4, 2019.
  6. DeVries T, Dentiste A, Handiwala L, Jacobs D. Bioavailability and pharmacokinetics of once-daily amantadine extended-release tablets in healthy volunteers: results from three randomized, crossover, open-label phase 1 studies. Neurol Ther. 2019. DOI: 10.1007/s40120-019-0144-1.