Last updated on RxList: 1/22/2021
Ongentys Side Effects Center

Medical Editor: John P. Cunha, DO, FACOEP

What Is Ongentys?

Ongentys (opicapone) is a catechol-O-methyltransferase (COMT) inhibitor used as adjunctive treatment to levodopa/carbidopa in patients with Parkinson's disease (PD) experiencing "off" episodes.

What Are Side Effects of Ongentys?

Side effects of Ongentys include:

Dosage for Ongentys

The recommended dosage of Ongentys is 50 mg administered orally once daily at bedtime.

Ongentys In Children

Safety and effectiveness of Ongentys in pediatric patients have not been established.

What Drugs, Substances, or Supplements Interact with Ongentys?

Ongentys may interact with other medicines such as:

  • monoamine oxidase inhibitors (MAOIs) and
  • drugs metabolized by catechol-o-methyltransferase (COMT)

Tell your doctor all medications and supplements you use.

Ongentys During Pregnancy and Breastfeeding

Tell your doctor if you are pregnant or plan to become pregnant before using Ongentys; it may harm a fetus. It is unknown if Ongentys passes into breast milk. Consult your doctor before breastfeeding.

Additional Information

Our Ongentys (opicapone) Capsules, for Oral Use Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.


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Ongentys Consumer Information

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • a light-headed feeling, like you might pass out;
  • confusion, hallucinations (hearing or seeing something that is not there);
  • aggression, agitation, unusual thoughts or behavior;
  • uncontrolled muscle movements in your face (chewing, lip smacking, frowning, tongue movement, blinking or eye movement); or
  • worsening tremors, stiffness, or muscle spasms.

You may have increased sexual urges, unusual urges to gamble, or other intense urges while taking this medicine. Talk with your doctor if this occurs.

Common side effects may include:

  • feeling light-headed;
  • uncontrolled muscle movement;
  • abnormal blood tests;
  • constipation; or
  • weight loss.

When you stop taking opicapone, watch for withdrawal symptoms such as: stiff muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, or feeling like you might pass out.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Read the entire detailed patient monograph for Ongentys (Opicapone Capsules)


Parkinson's disease is only seen in people of advanced age. See Answer
Ongentys Professional Information


The following clinically significant adverse reactions are discussed in more detail in other sections of the labeling:

  • Cardiovascular Effects with Concomitant Use of Drugs Metabolized by Catechol-O-Methyltransferase (COMT) [see WARNINGS AND PRECAUTIONS]
  • Falling Asleep During Activities of Daily Living and Somnolence [see WARNINGS AND PRECAUTIONS]
  • Hypotension/Syncope [see WARNINGS AND PRECAUTIONS]
  • Hallucinations and Psychosis [see WARNINGS AND PRECAUTIONS]
  • Impulse Control/Compulsive Disorders [see WARNINGS AND PRECAUTIONS]
  • Withdrawal-Emergent Hyperpyrexia and Confusion [see WARNINGS AND PRECAUTIONS]

Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

The safety of ONGENTYS was evaluated in 265 patients with Parkinson’s disease (PD) in two 14-15 week placebo-and active-controlled (Study 1) or placebo-controlled (Study 2) studies [see Clinical Studies]. All patients were taking a stable dose of levodopa and a DOPA decarboxylase inhibitor, alone or in combination with other PD medications. In Study 1 and Study 2, the mean age of patients was 63.6 years, 59% of patients were male, and 89% of patients were Caucasian. At baseline, the mean duration of PD was 7.6 years.

Adverse Reactions Leading To Discontinuation Of Treatment

In Study 1 and Study 2, a total of 8% of ONGENTYS 50 mg-treated patients and 6% of patients who received placebo discontinued due to adverse events. The most common adverse reaction leading to discontinuation was dyskinesia, reported in 3% of ONGENTYS 50 mg-treated patients and 0.4% of patients who received placebo.

Common Adverse Reactions

Adverse reactions that occurred in the pooled studies at an incidence of at least 2% and greater than placebo are presented in Table 1. The most common adverse reactions (incidence at least 4% and greater than placebo) were dyskinesia, constipation, blood creatine kinase increased, hypotension/syncope, and weight decreased.

Table 1: Adverse Reactions with an Incidence of at Least 2% in Patients Treated with ONGENTYS and Greater than on Placebo, in Pooled Study 1 and Study 2

Adverse ReactionsONGENTYS 50 mg
Nervous system disorders
Gastrointestinal disorders
  Dry mouth31
Psychiatric disorders
  Blood creatine kinase increased52
  Weight decreased40
Vascular disorders
1 Includes hallucinations, hallucinations visual, hallucinations auditory, and hallucinations mixed
2 Includes hypotension, orthostatic hypotension, syncope, and presyncope

Read the entire FDA prescribing information for Ongentys (Opicapone Capsules)

© Ongentys Patient Information is supplied by Cerner Multum, Inc. and Ongentys Consumer information is supplied by First Databank, Inc., used under license and subject to their respective copyrights.

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