Vitex and medications.
Vitex is in the Distil supplement database, evidence Grade B. The page below lists every medication we have explicitly assessed it against.
Vitex, also called chasteberry or agnus castus, is a fruit extract used mainly for premenstrual symptoms, working by gently modulating prolactin and hormone signalling. The evidence is Grade B for PMS and cyclical breast pain, which makes it one of the better-supported herbal options for the menstrual cycle, though trials are modest and individual response varies. The typical dose is 20 to 40mg of standardised dried fruit extract. It is meant for pre-menopausal women only: it is not appropriate after menopause and is contraindicated in pregnancy. The interactions worth knowing both relate to hormones and dopamine. Because it acts on dopamine pathways, it can interfere with dopamine agonists and antagonists, and it may interfere with oral contraceptives, so a GP caution note is warranted if you take the pill. Early on it can cause headache, stomach upset or an irregular cycle as things settle. Practically, give it three full cycles before deciding whether it helps.
Below are the 30 documented pairs we have explicitly assessed for Vitex: 30 amber. The pairs cluster around 3 mechanisms: Reduced antipsychotic effect, Dopaminergic potentiation (levodopa-sparing), and Hormonal axis modulation. Every call is cited to either a clinical reference (PMID) or the British National Formulary. Anything not listed here is either still to be assessed or beyond our database scope. The checker beneath surfaces assessments by medication, and the missing-item form at the bottom of the page routes any uncatalogued medication into our next curation pass.
Documented interactions
Reduced antipsychotic effect
Vitex (chasteberry) gently nudges the brain's dopamine system in the opposite direction to how antipsychotics like amisulpride work, so in theory it could work against the medication. Amisulpride is a medicine where the effect is watched closely, so if you take it, it is best not to add vitex without talking to the team that manages your medication first.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) acts gently on the brain's dopamine system, which can interact with how aripiprazole works. Because aripiprazole works on dopamine in a more balanced way than other antipsychotics, the effect of adding vitex is hard to predict, so it is worth discussing vitex with your prescriber before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) gently pushes the brain's dopamine system in the opposite direction to how asenapine works, so in theory it could work against the medication. If you take asenapine, it is best to discuss vitex with the team that manages your medication before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) acts gently on the brain's dopamine system, which can interact with how cariprazine works. Because cariprazine works on dopamine in a more balanced way than other antipsychotics, the effect of adding vitex is hard to predict, so it is worth discussing vitex with your prescriber before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) gently pushes the brain's dopamine system in the opposite direction to how chlorpromazine works, so in theory it could work against the medication. If you take chlorpromazine, it is best to discuss vitex with the team that manages your medication before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
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.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) gently pushes the brain's dopamine system in the opposite direction to how flupentixol works, so in theory it could work against the medication. If you take flupentixol, it is best to discuss vitex with the team that manages your medication before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) gently pushes the brain's dopamine system in the opposite direction to how haloperidol works, so in theory it could work against the medication. If you take haloperidol, it is best to discuss vitex with the team that manages your medication before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) gently pushes the brain's dopamine system in the opposite direction to how lurasidone works, so in theory it could work against the medication. If you take lurasidone, it is best to discuss vitex with your prescriber before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Metoclopramide works partly by blocking dopamine to settle nausea, and vitex (chasteberry) gently acts on the same dopamine system in the opposite direction, so in theory it could blunt the effect. This matters most if you take metoclopramide regularly rather than as a one-off. If in doubt, mention vitex to your prescriber.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) gently pushes the brain's dopamine system in the opposite direction to how olanzapine works, so in theory it could work against the medication. If you take olanzapine, discuss vitex with your prescriber before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) gently pushes the brain's dopamine system in the opposite direction to how paliperidone works, so in theory it could work against the medication. If you take paliperidone, it is best to discuss vitex with the team that manages your medication before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) gently pushes the brain's dopamine system in the opposite direction to how pimozide works, so in theory it could work against the medication. If you take pimozide, it is best to discuss vitex with the team that manages your medication before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Prochlorperazine works partly by blocking dopamine to settle nausea and dizziness, and vitex (chasteberry) gently acts on the same dopamine system in the opposite direction, so in theory it could blunt the effect. This matters most with regular use. If in doubt, mention vitex to your prescriber.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) gently nudges the brain's dopamine system, which can in theory work against antipsychotics. Quetiapine acts only loosely on dopamine, so any effect is likely small, but if you take it for a mental-health condition it is still worth mentioning vitex to your prescriber before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) gently pushes the brain's dopamine system in the opposite direction to how risperidone works, so in theory it could work against the medication. If you take risperidone, it is best to discuss vitex with the team that manages your medication before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) gently pushes the brain's dopamine system in the opposite direction to how sulpiride works, so in theory it could work against the medication. If you take sulpiride, it is best to discuss vitex with the team that manages your medication before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) gently pushes the brain's dopamine system in the opposite direction to how zuclopenthixol works, so in theory it could work against the medication. If you take zuclopenthixol, it is best to discuss vitex with the team that manages your medication before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Dopaminergic potentiation (levodopa-sparing)
Pramipexole works by boosting dopamine activity, and vitex (chasteberry) gently acts in the same direction, so the two could add together. If you take pramipexole for Parkinson's or restless legs, it is worth discussing vitex with your Parkinson's team rather than adding it yourself.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Ropinirole works by boosting dopamine activity, and vitex (chasteberry) gently acts in the same direction, so the two could add together. If you take ropinirole for Parkinson's or restless legs, it is worth discussing vitex with your Parkinson's team rather than adding it yourself.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Hormonal axis modulation
Vitex (chasteberry) acts on the body's hormone signals: it lowers prolactin and, in lab studies, gently nudges oestrogen and progesterone receptors. HRT with conjugated oestrogens works by topping up your hormones to ease menopausal symptoms, so in theory vitex could pull against that, and the HRT could equally blunt what vitex is meant to do. There is no study showing this actually happens, so it is a caution rather than a firm warning. If you take HRT, it is worth mentioning vitex to your prescriber before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) acts on hormone signals, lowering prolactin and gently nudging oestrogen and progesterone receptors in lab studies. The progestogen-only pill relies entirely on its progestogen, so in theory vitex could interfere with that balance. There is no study showing the pill fails when vitex is added, so this is a caution rather than a firm warning. If you take the progestogen-only pill, mention vitex to your prescriber before adding it, and treat any change in your bleeding pattern as a reason to check in.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) acts on the body's hormone signals: it lowers prolactin and, in lab studies, gently nudges oestrogen and progesterone receptors. Dydrogesterone is the progestogen in HRT combinations such as Femoston, so in theory vitex could pull against the hormone balance the HRT is providing, and the HRT could equally blunt what vitex is meant to do. There is no study showing this actually happens, so it is a caution rather than a firm warning. If you take HRT, it is worth mentioning vitex to your prescriber before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) acts on the body's hormone signals: it lowers prolactin and, in lab studies, gently nudges oestrogen and progesterone receptors. HRT works by topping up your hormones to ease menopausal symptoms, so in theory vitex could pull against that, and the HRT could equally blunt what vitex is meant to do. There is no study showing this actually happens, so it is a caution rather than a firm warning. If you take HRT, it is worth mentioning vitex to your prescriber before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) acts on the body's hormone signals: it lowers prolactin and, in lab studies, gently nudges oestrogen and progesterone receptors. Combined HRT tops up both oestrogen and progesterone to ease menopausal symptoms, so in theory vitex could pull against that balance, and the HRT could equally blunt what vitex is meant to do. There is no study showing this actually happens, so it is a caution rather than a firm warning. If you take combined HRT, it is worth mentioning vitex to your prescriber before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) acts on the body's hormone signals: it lowers prolactin and, in lab studies, gently nudges oestrogen and progesterone receptors. The combined pill works by holding your hormones at set levels, so in theory vitex could work against that balance, and the pill's hormones could equally blunt what vitex is meant to do. There is no study showing the pill actually fails when vitex is added, so this is a caution rather than a firm warning. If you take the combined pill, mention vitex to your prescriber before adding it, and treat any breakthrough bleeding as a reason to check in.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) acts on the body's hormone signals: it lowers the hormone prolactin and, in lab studies, gently nudges oestrogen and progesterone receptors. The combined pill works by holding your hormones at set levels, so in theory vitex could work against that balance, and the pill's hormones could equally blunt what vitex is meant to do. There is no study showing the pill actually fails when vitex is added, so this is a caution rather than a firm warning. If you take the combined pill, it is worth mentioning vitex to your prescriber before adding it, and treating any breakthrough bleeding as a reason to check in.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) acts on the body's hormone signals: it lowers prolactin and, in lab studies, gently nudges oestrogen and progesterone receptors. Medroxyprogesterone is a progestogen hormone medicine, so in theory vitex could pull against its hormonal effect. There is no study showing this actually happens, so it is a caution rather than a firm warning. If you take this medicine, it is worth mentioning vitex to your prescriber before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) acts on the body's hormone signals: it lowers prolactin and, in lab studies, gently nudges oestrogen and progesterone receptors. Norethisterone is a progestogen used in HRT and to control periods, so in theory vitex could pull against the hormone balance it is providing, and the medication could equally blunt what vitex is meant to do. There is no study showing this actually happens, so it is a caution rather than a firm warning. It is worth mentioning vitex to your prescriber before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Vitex (chasteberry) acts on the body's hormone signals: it lowers prolactin and, in lab studies, gently nudges oestrogen and progesterone receptors. Micronised progesterone is a progesterone hormone medicine (often part of HRT), so in theory vitex could pull against its hormonal effect. There is no study showing this actually happens, so it is a caution rather than a firm warning. If you take this medicine, it is worth mentioning vitex to your prescriber before adding it.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
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