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Allylamine antifungal (oral; onychomycosis, tinea)Reviewed May 22, 2026

Terbinafine (Lamisil) and Ketamine Therapy | Tovani Health

Lamisil (Terbinafine)Allylamine antifungal (oral; onychomycosis, tinea)

Verdict at Tovani Health

Fully compatible; the relevant drug interactions are with CYP2D6 substrates, not ketamine.

Oral terbinafine and ketamine have no clinically significant interaction. Different mechanism from the azole antifungals (fluconazole, itraconazole, ketoconazole) — terbinafine inhibits a fungal squalene epoxidase rather than CYP51. From a drug-interaction standpoint, terbinafine is a CYP2D6 inhibitor, which matters for metoprolol, propranolol, TCAs, codeine, tamoxifen, and other CYP2D6 substrates — but ketamine is primarily metabolized by CYP3A4 and CYP2B6 with only minor CYP2D6 contribution, so terbinafine's effect on ketamine is minimal. Hepatotoxicity monitoring during long courses (LFTs at baseline) is intrinsic to terbinafine.

If you take Lamisil 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 Lamisil interacts with ketamine

Terbinafine inhibits fungal squalene epoxidase, blocking ergosterol synthesis. Hepatic metabolism. CYP2D6 inhibitor — relevant for many psych and cardiac meds, not for ketamine.

What we do at intake

Continue your terbinafine course. Tell us about any LFT abnormalities or unexplained fatigue. If you're on metoprolol or a TCA, your prescriber should know about the CYP2D6 interaction (independent of KAP).

Bottom line

Oral terbinafine and ketamine have no clinically significant interaction. Different mechanism from the azole antifungals (fluconazole, itraconazole, ketoconazole) — terbinafine inhibits a fungal squalene epoxidase rather than CYP51. From a drug-interaction standpoint, terbinafine is a CYP2D6 inhibitor, which matters for metoprolol, propranolol, TCAs, codeine, tamoxifen, and other CYP2D6 substrates — but ketamine is primarily metabolized by CYP3A4 and CYP2B6 with only minor CYP2D6 contribution, so terbinafine's effect on ketamine is minimal. Hepatotoxicity monitoring during long courses (LFTs at baseline) is intrinsic to terbinafine.

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

We’ll note that you’re on Lamisil (Terbinafine) 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 22, 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.