Drug & supplement interaction

Vitex Agnus-castus + Interferon Beta-1a

Interferon Beta-1a brand names: Rebif, Avonex.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 20, 2026
The bottom line No known interaction

We found no known interaction between Vitex Agnus-castus and Interferon Beta-1a in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first.

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Interaction report

Vitex Agnus-castus and Interferon Beta-1a

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Interferon Beta-1a and Vitex Agnus-castus in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Vitex Agnus-castus safety at a glance

Vitex Agnus-castus overall Use caution Often well tolerated short-term, but it may affect hormones, so use under guidance.
Pregnancy Possibly Unsafe When used orally. Theoretically, the hormonal effects of vitex agnus-castus might adversely affect pregnancy or lactation. Animal research shows that taking vit... Read the full pregnancy detail
Breastfeeding Possibly Unsafe When used orally. Theoretically, the hormonal effects of vitex agnus-castus might adversely affect pregnancy or lactation. Animal research shows that taking vit... Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Interferon Beta-1a and Vitex Agnus-castus? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Interferon Beta-1a

Interactions in our licensed database are recorded against drug classes, not just single drug names. Interferon Beta-1a is filed under 2 classifications — photosensitizing drugs, hepatotoxic drugs. Vitex Agnus-castus has documented interactions with 5 drug classes — the most serious being antipsychotic drugs (moderate), contraceptive drugs (moderate) and dopamine agonists (moderate) — and none of Interferon Beta-1a’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Vitex Agnus-castus Does Interact With Other Medications

Vitex Agnus-castus has 121 moderate known drug interactions in our database — Interferon Beta-1a isn’t one of them. If you take anything else, check it against the full list below.

Moderate 121 No known interaction 2,709 (incl. Interferon Beta-1a)
Taking anything else?

Check Another of Your Medications Against Vitex Agnus-castus

Covers the 2,830 medications we’ve checked against Vitex Agnus-castus. Pick one to open its full report.

What to actually watch for

What Vitex Agnus-castus Itself Has Been Linked To

This is not an interaction — nothing below involves Interferon Beta-1a. It is the side-effect record for Vitex Agnus-castus on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Vitex Agnus-castus, this list is the first place to look. 3 entries are worth acting on rather than waiting out — marked below.

  • Confusion Worth acting on Additional detail

    “Orally, headache, fatigue, and insomnia, confusion, and vertigo have been reported.”

    Vitex Agnus-castus · Natural Medicines adverse-effect record, reported in cluster headache.

    6 sources cited
    1. 7076. Lauritzen CH, Reuter HD, Repges R, et al. Treatment of premenstrual tension syndrome with Vitex agnus castus: Controlled-double blind versus pyridoxine. Phytomedicine 1997;4:183-9.
    2. 7078. Berger D, Schaffner W, Schrader E, et al. Efficacy of Vitex agnus castus L. extract Ze 440 in patients with premenstrual syndrome (PMS). Arch Gynecol Obstet 2000;264:150-3.
    3. 12207. Atmaca M, Kumru S, Tezcan E. Fluoxetine versus Vitex agnus castus extract in the treatment of premenstrual dysphoric disorder. Hum Psychopharmacol 2003;18:191-5..
    4. 13393. Daniele C, Thompson Coon J, Pittler MH, Ernst E. Vitex agnus castus: a systematic review of adverse events. Drug Saf 2005;28:319-32..
    5. 13395. Halaska M, Beles P, Gorkow C, Sieder C. Treatment of cyclical mastalgia with a solution containing a Vitex agnus castus extract: results of a placebo-controlled double-blind study. Breast 1999;8:175-81. PubMed
    6. 15065. Prilepskaya VN, Ledina AV, Tagiyeva AV, Revazova FS. Vitex agnus castus: Successful treatment of moderate to severe premenstrual syndrome. Maturitas 2006;55 Suppl 1:S55-63. DOI
  • Hives Worth acting on Additional detail

    “Orally, skin conditions such as itching, irritation, urticaria, rash, acne, eczema, and hair loss have been reported.”

    Vitex Agnus-castus · Natural Medicines adverse-effect record, reported in acne.

    6 sources cited
    1. 7055. Schellenberg R. Treatment for the premenstrual syndrome with agnus castus fruit extract: prospective, randomised, placebo-controlled study. BMJ 2001;322:134-7. PubMed
    2. 7076. Lauritzen CH, Reuter HD, Repges R, et al. Treatment of premenstrual tension syndrome with Vitex agnus castus: Controlled-double blind versus pyridoxine. Phytomedicine 1997;4:183-9.
    3. 7078. Berger D, Schaffner W, Schrader E, et al. Efficacy of Vitex agnus castus L. extract Ze 440 in patients with premenstrual syndrome (PMS). Arch Gynecol Obstet 2000;264:150-3.
    4. 7079. Loch EG, Selle H, Boblitz N. Treatment of premenstrual syndrome with a phytopharmaceutical formulation containing Vitex agnus castus. J Womens Health Gend Based Med 2000;9:315-20. PubMed
    5. 12207. Atmaca M, Kumru S, Tezcan E. Fluoxetine versus Vitex agnus castus extract in the treatment of premenstrual dysphoric disorder. Hum Psychopharmacol 2003;18:191-5..
    6. 13393. Daniele C, Thompson Coon J, Pittler MH, Ernst E. Vitex agnus castus: a systematic review of adverse events. Drug Saf 2005;28:319-32..
  • Bleeding or bruising Worth acting on Additional detail

    “Orally, irregular or prolonged menstrual bleeding has been reported.”

    Vitex Agnus-castus · Natural Medicines adverse-effect record, reported in bleeding.

    6 sources cited
    1. 7055. Schellenberg R. Treatment for the premenstrual syndrome with agnus castus fruit extract: prospective, randomised, placebo-controlled study. BMJ 2001;322:134-7. PubMed
    2. 7079. Loch EG, Selle H, Boblitz N. Treatment of premenstrual syndrome with a phytopharmaceutical formulation containing Vitex agnus castus. J Womens Health Gend Based Med 2000;9:315-20. PubMed
    3. 12207. Atmaca M, Kumru S, Tezcan E. Fluoxetine versus Vitex agnus castus extract in the treatment of premenstrual dysphoric disorder. Hum Psychopharmacol 2003;18:191-5..
    4. 13393. Daniele C, Thompson Coon J, Pittler MH, Ernst E. Vitex agnus castus: a systematic review of adverse events. Drug Saf 2005;28:319-32..
    5. 15065. Prilepskaya VN, Ledina AV, Tagiyeva AV, Revazova FS. Vitex agnus castus: Successful treatment of moderate to severe premenstrual syndrome. Maturitas 2006;55 Suppl 1:S55-63. DOI
    6. 41489. Ma, L., Lin, S., Chen, R., and Wang, X. Treatment of moderate to severe premenstrual syndrome with Vitex agnus castus (BNO 1095) in Chinese women. Gynecol.Endocrinol. 2010;26(8):612-616. PubMed
  • Acne / Hair loss / Itching Additional detail

    Recorded for Vitex Agnus-castus in the same Natural Medicines adverse-effect record shown under Hives above.

  • Trouble sleeping / Tiredness Additional detail

    “Orally, vitex agnus-castus is generally well tolerated.

    Most Common Adverse Effects:

    Orally: Diarrhea, fatigue, headache, insomnia, irregular menstruation, nausea, skin irritation, stomach pain, vomiting.”

    Vitex Agnus-castus · Natural Medicines adverse-effect record, reported in cluster headache.

  • Stomach upset Additional detail

    “Orally, gastrointestinal upset or pain, diarrhea, and nausea and vomiting, have been reported. In one clinical trial, a single patient reported persistent gastroenteritis while taking vitex agnus-castus. Orally, development of a bezoar resulting in colonic obstruction is described in a 63-year-old male who consumed an unknown amount of vitex agnus-castus seeds.”

    Vitex Agnus-castus · Natural Medicines adverse-effect record, reported in diarrhea.

    6 sources cited
    1. 7079. Loch EG, Selle H, Boblitz N. Treatment of premenstrual syndrome with a phytopharmaceutical formulation containing Vitex agnus castus. J Womens Health Gend Based Med 2000;9:315-20. PubMed
    2. 12207. Atmaca M, Kumru S, Tezcan E. Fluoxetine versus Vitex agnus castus extract in the treatment of premenstrual dysphoric disorder. Hum Psychopharmacol 2003;18:191-5..
    3. 13393. Daniele C, Thompson Coon J, Pittler MH, Ernst E. Vitex agnus castus: a systematic review of adverse events. Drug Saf 2005;28:319-32..
    4. 15065. Prilepskaya VN, Ledina AV, Tagiyeva AV, Revazova FS. Vitex agnus castus: Successful treatment of moderate to severe premenstrual syndrome. Maturitas 2006;55 Suppl 1:S55-63. DOI
    5. 90620. Yavarikia P, Shahnazi M, Hadavand Mirzaie S, Javadzadeh Y, Lutfi R. Comparing the effect of mefenamic Acid and vitex agnus on intrauterine device induced bleeding. J Caring Sci. 2013 Aug 31;2(3):245-54.
    6. 101981. Ooi SL, Watts S, McClean R, Pak SC. Vitex agnus-castus for the treatment of cyclic mastalgia: A systematic review and meta-analysis. J Womens Health (Larchmt). 2020;29(2):262-278. PubMed
  • Stomach pain Additional detail

    Recorded for Vitex Agnus-castus in the same Natural Medicines adverse-effect record shown under Trouble sleeping / Tiredness above.

Showing the 10 most notable of 16 recorded effects — ranked by how unusual each one is across medicines generally, with serious effects weighted up.

Everything above comes from the Natural Medicines adverse-effect record for Vitex Agnus-castus — expand a row for the licensed statement it rests on. We haven’t matched Interferon Beta-1a to its FDA label in our system yet, so we can’t compare its own side-effect list here — the leaflet that comes with your prescription is the authoritative list for Interferon Beta-1a.

Special populations

Vitex Agnus-castus in Pregnancy & Breastfeeding

Pregnancy And Lactation Possibly Unsafe

When used orally. Theoretically, the hormonal effects of vitex agnus-castus might adversely affect pregnancy or lactation. Animal research shows that taking vitex agnus-castus fruit extract when planning to become pregnant or during pregnancy may increase the risk of infertility, low fetal body weight, abortion, and stillbirth; avoid using.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center

Everything else you take

See Every Supplement That Interacts With Interferon Beta-1a

This page covers Vitex Agnus-castus only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Interferon Beta-1a page lists 57 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Beer (major), Siberian Cocklebur (major), Wine (major), Alfalfa (moderate) and Angelica Archangelica (moderate).

By severity: 3 major · 53 moderate · 1 minor.

From our pharmacist’s overview on the Interferon Beta-1a page

“Siberian cocklebur, an herb tied to documented cases of liver failure, is the first name to know for anyone injecting interferon beta-1a (Rebif, Avonex) for multiple sclerosis. Interferon beta-1a can strain the liver on its own, which is why prescribers order routine liver blood tests, and 38 of the 57 supplements on file carry that sa…”

Reviewed by 2 · Jul 18, 2026

Open the Interferon Beta-1a interaction page

One more smart check

Taking Vitex Agnus-castus as Part of a Dietary Supplement Product? Check It for Interactions

We hold 45 real supplement products containing Vitex Agnus-castus, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Vitex Agnus-castus. Even though Vitex Agnus-castus itself has no known interaction with Interferon Beta-1a, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Vitex Agnus-castus and Interferon Beta-1a Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Vitex Agnus-castus
Top half

#509 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Interferon Beta-1a
Steady interest

#2,614 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Vitex Agnus-castus reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Vitex Agnus-castus and Interferon Beta-1a records this page draws on were last updated July 10, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About Vitex Agnus-castus

What is Vitex Agnus-castus?

Vitex Agnus-castus
  • Premenstrual syndrome (PMS)
  • Irregular or absent menstrual periods
  • Cyclical breast pain (mastalgia)
  • Menopause symptoms
  • Fertility support

Vitex (chasteberry) is an herbal remedy most often used for PMS and menstrual cycle problems, and the strongest evidence is for easing some PMS symptoms. It is generally well tolerated by many adults, but it can affect hormone-related processes, so anyone who is pregnant, breastfeeding, or has a hormone-sensitive condition should talk with a healthcare professional first.

Vitex agnus-castus · Lamiaceae · Dried ripe fruit (berries) · Capsules, tablets, liquid extracts (tinctures), and teas

An interaction check asks whether these two react with each other — it does not ask whether Vitex Agnus-castus is a good idea for someone in your situation. Here is what our Vitex Agnus-castus record says about it on its own.

Vitex Agnus-castus: dosing

There is no single official or proven dose for vitex. Products differ widely in how they are made and how concentrated they are, so the amount per dose varies from one brand to another. Standardized extracts are common, but a universal best dose has not been established.The safest approach is to follow the directions on the product label and not take more than recommended. Because vitex may take several weeks or even a few menstrual cycles before any effect is noticed, it is often used over time.

From our Vitex Agnus-castus monograph — the full record covers uses, side effects and every documented interaction.

Read the full Vitex Agnus-castus monograph & all interactions
Medication

About Interferon Beta-1a Intramuscular Injection

What Is Interferon Beta-1a Intramuscular Injection Used For?

Brand names: Rebif, Avonex

  • Interferon beta-1a intramuscular injection is used to treat adults with various forms of multiple sclerosis (MS; a disease in which the nerves do not function properly and people may experience weakness, numbness, loss of muscle coordination, and problems with vision, speech, and bladder control) including:

    • clinically isolated syndrome (CIS; nerve symptom episodes that last at least 24 hours),

    • relapsing-remitting forms (course of disease where symptoms flare up from time to time), or

    • secondary progressive forms (course of disease where relapses occur more often).

  • Interferon beta-1a is in a class of medications called immunomodulators. It works by decreasing inflammation and preventing nerve damage that may cause symptoms of multiple sclerosis.

Most-Reported Side Effects for Interferon Beta-1a

From FAERS, the FDA’s public side-effect reporting system (192,069 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Multiple sclerosis relapse 15,851 reports
Influenza like illness 13,253 reports
Fatigue 11,554 reports
Fall 10,604 reports
Multiple sclerosis 9,358 reports
See full Interferon Beta-1a Intramuscular Injection drug information
Keep checking

Other Drugs & Vitex Agnus-castus

Browse every other medication we’ve checked against Vitex Agnus-castus — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
121Moderate
0Minor
2,708No known interaction
121 Moderate 2,708 No interaction
Moderate

121 interactions

Showing 60 of 121 moderate interactions — see all 121 on the Vitex Agnus-castus page.

No interaction 2,708 drugs checked — show the list

We also checked Vitex Agnus-castus against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,708 medications checked with no known interaction — see the full Vitex Agnus-castus list.

See the full Vitex Agnus-castus interactions page
See every supplement checked against Interferon Beta-1a, ranked by severity
Evidence & sources

Vitex Agnus-castus References

The 23 references that drive our Vitex Agnus-castus monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  1. Wuttke W. Dopaminergic action of extracts of Agnus Castus. Forschende Komplementarmedizen 1996;3:329-30.
  2. Jarry H, Leonhardt S., Gorkow C, Wuttke W. In vitro prolactin but not LH and FSH release is inhibited by compounds in extracts of Agnus Castus: direct evidence for a dopaminergic principle by the dopamine receptor assay. Exp Clin Endocrinol 1994;102:448- PubMed
  3. Schellenberg R. Treatment for the premenstrual syndrome with agnus castus fruit extract: prospective, randomised, placebo-controlled study. BMJ 2001;322:134-7. PubMed
  4. Lauritzen CH, Reuter HD, Repges R, et al. Treatment of premenstrual tension syndrome with Vitex agnus castus: Controlled-double blind versus pyridoxine. Phytomedicine 1997;4:183-9.
  5. Berger D, Schaffner W, Schrader E, et al. Efficacy of Vitex agnus castus L. extract Ze 440 in patients with premenstrual syndrome (PMS). Arch Gynecol Obstet 2000;264:150-3.
  6. Loch EG, Selle H, Boblitz N. Treatment of premenstrual syndrome with a phytopharmaceutical formulation containing Vitex agnus castus. J Womens Health Gend Based Med 2000;9:315-20. PubMed
  7. Meier B, Berger D, Hoberg E, et al. Pharmacological activities of Vitex agnus-castus extracts in vitro. Phytomedicine 2000;7:373-81. PubMed
  8. Liu J, Burdette JE, Xu H, et al. Evaluation of estrogenic activity of plant extracts for the potential treatment of menopausal symptoms. J Agric Food Chem 2001;49:2472-9.. PubMed
  9. Wuttke W, Jarry H, Christoffel V, et al. Chaste tree (Vitex agnus-castus)--pharmacology and clinical indications. Phytomedicine 2003;10:348-57. PubMed
  10. Atmaca M, Kumru S, Tezcan E. Fluoxetine versus Vitex agnus castus extract in the treatment of premenstrual dysphoric disorder. Hum Psychopharmacol 2003;18:191-5..
  11. Daniele C, Thompson Coon J, Pittler MH, Ernst E. Vitex agnus castus: a systematic review of adverse events. Drug Saf 2005;28:319-32..
  12. Halaska M, Beles P, Gorkow C, Sieder C. Treatment of cyclical mastalgia with a solution containing a Vitex agnus castus extract: results of a placebo-controlled double-blind study. Breast 1999;8:175-81. PubMed
  13. Prilepskaya VN, Ledina AV, Tagiyeva AV, Revazova FS. Vitex agnus castus: Successful treatment of moderate to severe premenstrual syndrome. Maturitas 2006;55 Suppl 1:S55-63. DOI
  14. Ma, L., Lin, S., Chen, R., and Wang, X. Treatment of moderate to severe premenstrual syndrome with Vitex agnus castus (BNO 1095) in Chinese women. Gynecol.Endocrinol. 2010;26(8):612-616. PubMed
  15. Ma, L., Lin, S., Chen, R., Zhang, Y., Chen, F., and Wang, X. Evaluating therapeutic effect in symptoms of moderate-to-severe premenstrual syndrome with Vitex agnus castus (BNO 1095) in Chinese women. Aust.N.Z.J Obstet.Gynaecol. 2010;50(2):189-193. PubMed

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Vitex Agnus-castus and Interferon Beta-1a Together: Common Questions

Is it safe to take Vitex Agnus-castus with Interferon Beta-1a?
We do not list a known interaction between Vitex Agnus-castus and Interferon Beta-1a. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
How was the Vitex Agnus-castus and Interferon Beta-1a combination checked?
Interactions in our licensed database are recorded against drug classes. Interferon Beta-1a is filed under 2 classifications, and Vitex Agnus-castus has documented interactions with 5 drug classes — none of Interferon Beta-1a's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Vitex Agnus-castus interact with any other medications?
Yes. Vitex Agnus-castus has 121 documented drug interactions in our database — Interferon Beta-1a is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Interferon Beta-1a interact with any supplements?
Yes. Interferon Beta-1a has documented interactions with 57 supplements in our database — Vitex Agnus-castus is not one of them. The Interferon Beta-1a interaction page linked on this page lists every one, ranked by severity.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Where next

Keep Exploring

Vitex Agnus-castus monograph Uses, safety profile, and every drug interaction in one place Interferon Beta-1a Intramuscular Injection drug information The full plain-English guide to this medication Interferon Beta-1a supplement interactions Every supplement checked against Interferon Beta-1a, ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 23 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.