Skip to Main Content Skip to Site Map Skip to Accessibility Statement Catechol-O-methyltransferase inhibitors (COMT inhibitors)

Formulary choicesEntacapone tablets 200mgDose: See BNF - seek specialist advice
Opicapone 50mg capsules Dose: See BNF - seek specialist advice
Tolcapone 100mg tablets Dose: See BNF and Shared Care Guideline- seek specialist advice as per notes below

Prescribing Notes

  • Note the difference in dosage instructions between COMT inhibitors. Entacapone is taken at the same time as levodopa medication. Opicapone is taken once a day at bedtime, at least 1 hour before or after levodopa medication.
  • A triple combination preparation of levodopa, carbidopa and entacapone may be suitable for patients requiring entacapone who are having problems with concordance. Prescribe by brand – Sastravi® and Stanek®  are currently the ‘branded generic’ combination preparations with the lowest acquisition cost.
  • Due to the risk of hepatotoxicity, tolcapone should be prescribed under specialist supervision only, when other COMT inhibitors combined with co-beneldopa or co-careldopa are ineffective or not tolerated. LFT monitoring is required (see shared care guideline).
  • The levodopa dose may need to be adjusted when a COMT inhibitor is initiated.
  • Tolcapone should only be continued beyond three weeks if there is substantial improvement in symptom control.