Supplements and Clozapine.
Clozapine, sold under the brand names Clozaril, Denzapine, Zaponex, is an antipsychotic: it antagonises dopamine D2 receptors and (for atypicals) serotonin receptors.
Clozapine is an antipsychotic medicine. The class divides into typicals (haloperidol, chlorpromazine, older agents) and atypicals (olanzapine, quetiapine, risperidone, aripiprazole, the newer agents). Both block dopamine D2 receptors. The atypicals add 5-HT2 receptor blockade and a different side effect profile. Most UK community prescribing is atypicals. The supplement surface includes three patterns: additive sedation (especially with quetiapine), QT prolongation (haloperidol, ziprasidone, some others), and CYP interactions for the more 3A4-sensitive agents in the class. Metabolic side effects (weight gain, glucose dysregulation, lipid effects) underpin the routine monitoring that NICE NG178 recommends. St John's Wort is flagged by the BNF across the class given enzyme induction concerns. Specific supplements with the closest serotonergic overlap (5-HTP, SAMe at high dose, saffron extract) warrant care, particularly alongside atypicals with significant 5-HT2 activity.
Below are the 3 documented pairs we have explicitly assessed against Clozapine in the Distil database: 3 caution. The pairs cluster around 2 mechanisms: Reduced antipsychotic effect and CYP1A2 induction. 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 lists the evidence its assessment drew on: some rest on studies of the exact pair, others on mechanism evidence, where a citation may support one part of the reasoning rather than the exact combination. The evidence line on each entry says which.
Reduced antipsychotic effect
Caution Does Glycine interact with Clozapine?
High-dose glycine taken alongside clozapine may work against the clozapine, making it less effective at controlling psychotic symptoms. This was seen in studies using very large glycine doses (30 to 60 grams a day), far above a typical glycine supplement. If you take clozapine, it is best not to add high-dose glycine, and to discuss any glycine supplement with the team that manages your medication, because clozapine is closely monitored.
Evidence: Supported by human study data.
Caution Does Vitex interact with Clozapine?
Vitex (chasteberry) gently nudges the brain's dopamine system in the opposite direction to how clozapine works, so in theory it could work against the medication. Clozapine is a closely monitored medicine, so do not add vitex without first discussing it with the team that manages your clozapine.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
CYP1A2 induction
Caution Does Resveratrol interact with Clozapine?
Resveratrol may speed up how the body clears clozapine, which could lower clozapine levels and reduce how well it works. Clozapine is carefully dose-managed, so do not change supplements without telling the team that monitors your clozapine.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
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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How the checker decides
Every result has a source
Each pair we have assessed is cited to a published study (PMID) or the British National Formulary, so you can read the source yourself.
Four kinds of answer
Severe, caution, no known interaction, and not yet assessed. A pair we have not assessed is never shown as clear.
- Severe
- Caution
- No known interaction
- Not yet assessed
Nothing in our data is not a clearance
When nothing in our data records a problem with a pair, the result says no known interaction at typical doses, which is not a clearance: your pharmacist or GP can check the pair against your full medical history.
A full supplement review, built around you, not a generic stack.
The free checker answers one interaction question at a time. A Distil report reviews the bigger picture: your goals, diet, medications, current supplements and any blood results you provide, then shows what appears worth keeping, changing, adding or leaving out.
- what your diet already covers, so you are not adding a capsule for something food is already handling
- which evidence-graded compounds are worth considering for your goals, and which were considered but left out
- what to keep, change or stop from what you already take, plus the order to introduce anything new
- how your medications and complete supplement stack fit together, with daily timing and a clear point for reassessment
The interaction check is one section of the full report. You also get the reasoning behind each recommendation and the evidence references used.
£49 until 30 June 2027 · £79 from 1 July 2027.
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