Comtan Drug Interactions

No interaction of entacapone with carbidopa has been observed with the recommended treatment schedule. Pharmacokinetic interaction with benserazide has not been studied.
In single-dose studies in healthy volunteers, no interactions were observed between entacapone and imipramine or between entacapone and moclobemide. Similarly, no interactions between entacapone and selegiline were observed in repeated-dose studies in parkinsonian patients. However, the experience of the clinical use of entacapone with several drugs, including MAO-A inhibitors, tricyclic antidepressants, noradrenaline re-uptake inhibitors eg, desipramine, maprotiline and venlafaxine, and catechol-structured medicinal products that are metabolised by COMT is still limited. Concomitant use of entacapone with these medicinal products is not recommended (see Contraindications and Precautions).
Entacapone may form chelates with iron in the gastrointestinal tract. Entacapone and iron preparations should be taken at least 2-3 hrs apart (see Adverse Reactions).
Entacapone binds to human albumin binding site II which also binds several other medicinal products, including diazepam and ibuprofen. Clinical interaction studies with diazepam and nonsteroidal anti-inflammatory drugs have not been carried out. According to in vitro studies, significant displacement is not anticipated at therapeutic concentrations of the medicinal products.
Incompatibilities: Not applicable.