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Pyrimidine antimetabolite chemotherapy (colorectal, breast, head/neck cancer; topical actinic keratosis)Reviewed May 23, 2026

5-Fluorouracil (5-FU, Adrucil, Efudex) and Ketamine Therapy | Tovani Health

Adrucil (IV) (5-Fluorouracil) (also: Efudex (topical), Carac (topical))Pyrimidine antimetabolite chemotherapy (colorectal, breast, head/neck cancer; topical actinic keratosis)

Verdict at Tovani Health

Fully compatible with KAP; DPD-deficiency toxicity screening is intrinsic to 5-FU.

5-Fluorouracil and ketamine have no clinically significant interaction. Backbone of colorectal cancer chemotherapy (FOLFOX, FOLFIRI), used across many other cancers as IV infusion, and as topical Efudex/Carac for actinic keratosis. The intrinsic considerations — mucositis, diarrhea, hand-foot syndrome, myelosuppression, and the severe toxicity in patients with DPD (dihydropyrimidine dehydrogenase) deficiency (now screened pre-treatment) — are 5-FU class issues independent of KAP.

If you take Adrucil (IV) 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 Adrucil (IV) interacts with ketamine

Inhibits thymidylate synthase, blocking DNA synthesis. DPD enzyme catabolizes 80% of 5-FU; deficiency causes life-threatening toxicity. Minimal CYP involvement; no interaction with ketamine.

What we do at intake

Continue your chemo regimen. Confirm DPD status was checked at initiation (intrinsic). For topical 5-FU, the skin reaction is normal and expected.

Bottom line

5-Fluorouracil and ketamine have no clinically significant interaction. Backbone of colorectal cancer chemotherapy (FOLFOX, FOLFIRI), used across many other cancers as IV infusion, and as topical Efudex/Carac for actinic keratosis. The intrinsic considerations — mucositis, diarrhea, hand-foot syndrome, myelosuppression, and the severe toxicity in patients with DPD (dihydropyrimidine dehydrogenase) deficiency (now screened pre-treatment) — are 5-FU class issues independent of KAP.

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

We’ll note that you’re on Adrucil (IV) (5-Fluorouracil) 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.