Entacapone

57 interactions 119 cited references
Also sold as: Comtan Comtan®
About Entacapone

Entacapone is a COMT inhibitor used with other Parkinson's medications to reduce end-of-dose symptom worsening. Read the full Entacapone drug information page →

Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated Aug 9, 2026 · Editorial policy · Data sources

Sources: FDA prescribing information (Structured Product Labeling), the published literature cited in each entry, DDInter 2.0 (a major open-access drug-interaction database), and legacy DrugBank interaction data distributed by the NIH's RxNav service (decommissioned in 2024) — analyzed and reviewed by our pharmacist team. How we build this library →

Most serious with: Furazolidone Nialamide Methylene Blue Linezolid Isocarboxazid Iproniazid
11 Contraindicated 26 Major 20 Moderate
All (57) Contraindicated (11) Major (26) Moderate (20)

Moderate

Entacapone Ampicillin Amcill® An increased risk of enhanced entacapone adverse effects (diarrhea, dyskinesias) Details Entacapone Ampicillin Injection Omnipen-N® An increased risk of enhanced entacapone adverse effects (diarrhea, dyskinesias) Details Entacapone Chloramphenicol Injection Chloromycetin® Injection An increased risk of enhanced entacapone adverse effects (diarrhea, dyskinesias) Details Entacapone Cholestyramine Resin Locholest® Enhanced entacapone adverse effects (diarrhea, dyskinesias) Details Entacapone Cyclophosphamide Cytoxan® Decreased activation of cyclophosphamide to 4-hydroxycyclophosphamide and risk for increased serum bilirubin and creatinine Details Entacapone Cyclophosphamide Injection Cytoxan® Injection Decreased activation of cyclophosphamide to 4-hydroxycyclophosphamide and risk for increased serum bilirubin and creatinine Details Entacapone Diclofenac Ophthalmic Voltaren® Eye Drops Increased diclofenac exposure Details Entacapone Diclofenac Topical (Actinic Keratosis) Pennsaid Increased diclofenac exposure Details Entacapone Diclofenac Topical (Arthritis Pain) Pennsaid® Increased diclofenac exposure Details Entacapone Diclofenac Transdermal Patch Flector Increased diclofenac exposure Details Entacapone Aceclofenac Increased diclofenac exposure Details Entacapone Celecoxib Celebrex Increased celecoxib exposure Details Entacapone Chloramphenicol An increased risk of enhanced entacapone adverse effects (diarrhea, dyskinesias) Details Entacapone Cholestyramine Prevalite Enhanced entacapone adverse effects (diarrhea, dyskinesias) Details Entacapone Diclofenac Aleve Arthritis Pain Increased diclofenac exposure Details Entacapone Erythromycin Erythrocin Stearate An increased risk of enhanced entacapone adverse effects (diarrhea, dyskinesias) Details Entacapone Iron Decreased entacapone bioavailability Details Entacapone Probenecid An increased risk of enhanced entacapone adverse effects (diarrhea, dyskinesias) Details Entacapone Rifampin Rifadin An increased risk of enhanced entacapone adverse effects (diarrhea, dyskinesias) Details Entacapone Sultamicillin An increased risk of enhanced entacapone adverse effects (diarrhea, dyskinesias) Details

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