Does Huperzine A interact with Cyclizine hydrochloride?

Medication · other drugs used in nausea and vertigo

Supplements and Cyclizine hydrochloride.

Every documented pair, every citation. Below: 1 documented pair grouped by mechanism.

Cyclizine hydrochloride, sold under the brand name Valoid, is classified under "drugs used in nausea and vertigo" in the BNF.

Cyclizine hydrochloride (brand names Valoid) sits at NHSBSA prescribing rank 139 in the 2024/25 PCA statistics. The BNF classifies it under "drugs used in nausea and vertigo". This means it sits outside the high-volume therapeutic classes (statins, PPIs, ACE inhibitors, SSRIs) where supplement-interaction surfaces are densely studied, and the published evidence base for specific supplement pairs is correspondingly thinner. Where interactions are documented in the Distil database, they are listed below with their clinical-reference citation; where pairs have not been explicitly assessed, the missing-item form at the bottom of the page routes them into our next curation pass. Anyone combining Cyclizine hydrochloride with a regular supplement stack benefits from explicit GP or pharmacist awareness rather than assuming no interaction exists by default.

Below are the 1 documented pair we have explicitly assessed against Cyclizine hydrochloride in the Distil database: 1 amber. The pairs cluster around 1 mechanism: Cholinergic vs anticholinergic (opposing). Every call is cited to either a clinical reference (PMID) or the British National Formulary. Anything not on this list is either still to be assessed or beyond our database scope. The checker beneath surfaces assessments by supplement, and the missing-item form at the bottom of the page routes any uncatalogued supplement into our next curation pass.

Documented interactions

Last reviewed 15 June 2026. Each interaction below is assessed against PubMed-indexed evidence.

Cholinergic vs anticholinergic (opposing)

Amber Does Huperzine A interact with ?

Huperzine A raises acetylcholine, while cyclizine (an antihistamine used for nausea) has an anticholinergic effect that blocks it. The two can work against each other, so cyclizine may blunt any benefit from huperzine A. It is worth mentioning the huperzine A to your prescriber.

Evidence: Based on an established mechanism, with no direct study of this exact combination yet.

PMID 29350336 · PMID 18425924 · BNF: Cyclizine

Reviewer-flagged: awaiting clinical-reviewer sign-off.

What this list does not say. Pairs not flagged here are not implicitly safe. They are either not yet in our database, or fall outside our inclusion scope (food-supplement interactions only; for drug-drug interactions, the BNF is authoritative). Use the checker below to surface any supplement, and submit a missing item if you take something we have not catalogued.

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For adults over 18. This tool gives evidence-graded information, not medical advice. Always discuss changes with your GP or pharmacist, especially if you take any medication, are pregnant, breastfeeding, or have a serious health condition.

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