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COMT inhibitor (Parkinson's, levodopa adjunct)Reviewed May 23, 2026

Entacapone (Comtan, Stalevo) and Ketamine Therapy | Tovani Health

Comtan (Entacapone) (also: Stalevo (with levodopa-carbidopa))COMT inhibitor (Parkinson's, levodopa adjunct)

Verdict at Tovani Health

Fully compatible with KAP — works alongside levodopa-carbidopa to extend levodopa effect.

Entacapone and ketamine have no clinically significant interaction. COMT inhibitor used adjunct to levodopa-carbidopa (combined as Stalevo) to extend levodopa's effect by blocking peripheral catechol-O-methyltransferase. The intrinsic 'entacapone gives urine a harmless brown-orange color' note is well-known and shouldn't be confused with hematuria. Hepatotoxicity surveillance was a concern with the related drug tolcapone (now rarely used); not a meaningful concern with entacapone.

If you take Comtan regularly and are considering at-home ketamine therapy, the combination is generally safe at therapeutic doses. This page covers the brief pharmacologic context and what we do at intake.

How Comtan interacts with ketamine

Selective, reversible COMT inhibitor blocking peripheral catechol-O-methylation, extending levodopa effect and reducing 'wearing off.' Hepatic glucuronidation. No clinically significant CYP interaction with ketamine.

What we do at intake

Continue per your neurologist's regimen. The orange-brown urine is expected.

Bottom line

Entacapone and ketamine have no clinically significant interaction. COMT inhibitor used adjunct to levodopa-carbidopa (combined as Stalevo) to extend levodopa's effect by blocking peripheral catechol-O-methyltransferase. The intrinsic 'entacapone gives urine a harmless brown-orange color' note is well-known and shouldn't be confused with hematuria. Hepatotoxicity surveillance was a concern with the related drug tolcapone (now rarely used); not a meaningful concern with entacapone.

Ready to find out if at-home ketamine fits your situation?

We’ll note that you’re on Comtan (Entacapone) at intake. The eligibility check takes 5 minutes and gives you an honest answer about whether at-home ketamine fits your specific situation.

FL and NJ residents only. Benjamin Soffer, DO — Tovani Health.

Clinically reviewed

Reviewed by Benjamin Soffer, DO on May 23, 2026. Dr. Soffer is a board-certified physician (American Board of Internal Medicine) licensed in Florida and New Jersey, prescribing at-home ketamine therapy through Tovani Health.

This page is general information about how this medication interacts with at-home ketamine therapy at Tovani Health. It is not a substitute for medical advice from your prescribing physician about your specific situation. Always discuss medication changes with the doctor who prescribed them.