Skip to main content


In April 2020, the U.S. Food and Drug Administration (FDA) approved Ongentys (opicapone) to use, with levodopa, to lessen the total amount of “off” time, when Parkinson’s symptoms return, each day. Ongentys is a catechol-O-methyltransferase (COMT) inhibitor, which prevents levodopa breakdown so that more gets to the brain and turns into dopamine. Dopamine is the brain chemical that fuels normal movement and decreases in Parkinson’s disease. Because Ongentys works by boosting levodopa’s effect, it must be added to a medication regimen containing levodopa. (It does not work on its own.)


Ongentys is taken once daily. (Other COMT-inhibitors must be taken several times a day or with each levodopa dose.) In clinical trials, Ongentys increased daily “on” time (when symptoms are controlled) by an average of one hour and was “non-inferior” to (no less effective than) Comtan (entacapone), another COMT-inhibitor.

Cons and Complications

Possible side effects may include dyskinesia (involuntary movement), difficulty sleeping, sleepiness, abnormal dreams, dizziness, headache, low blood pressure, constipation, vomiting, dry mouth, muscle spasms or hallucinations (seeing things that aren’t there). Some possible complications, such as dyskinesia, may relate to the levodopa boost rather than a direct effect of Ongentys.

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.

We use cookies to ensure that you get the best experience. By continuing to use this website, you indicate that you have read our Terms of Service and Privacy Policy.