Dong quai and chasteberry: what they do for PMS and PMDD

Dong quai (Angelica sinensis) is a root used in traditional Chinese medicine, often for menstrual cramps, hot flashes and general women's health complaints. Chasteberry (Vitex agnus-castus), sometimes called monk's pepper, comes from the dried fruit of the chaste tree and has a longer history of being studied specifically for premenstrual symptoms.

The two get bundled together in search results and supplement aisles, but they aren't interchangeable. Chasteberry has placebo-controlled trials behind it for one specific premenstrual symptom: breast tenderness, known as mastodynia [1]. Dong quai hasn't been tested that way for PMS or PMDD in the research covered on this page.

If you're new to the basics, what is PMS? explains the difference between everyday premenstrual symptoms and PMDD. That difference matters more here than the fact both herbs get sold under the same 'PMS support' label.

Dong quai doesn't have quality randomized trials testing it against placebo for PMS or PMDD symptoms in the research reviewed for this page. That doesn't mean it definitely does nothing, just that the kind of evidence that would settle the question hasn't turned up here.

PMDD is a specific diagnosis: at least five symptoms, including a mood symptom like irritability, anxiety or low mood, in the week before your period, confirmed by daily tracking over two cycles. Herbal supplements marketed broadly for 'women's health' are rarely tested against that bar.

If mood swings, anger or anxiety show up like clockwork before your period, a DRSP chart will tell you more in two cycles than trying a supplement and guessing. If it's costing you a week of every month, finding a PMDD specialist is worth more than any herb.

Chasteberry's research base is narrower than its reputation suggests. The placebo-controlled research behind it tested one mechanism: chasteberry extract appears to lower prolactin release from the pituitary gland, which can ease breast pain that flares before a period [1].

That's a real finding, but it's about breast tenderness, not anger, crying or the mood symptoms that define PMDD. The same research links this prolactin pattern to corpus luteum problems tied to fertility, a separate issue from mood.

So if your main premenstrual complaint is sore, heavy breasts, chasteberry has more evidence behind it than dong quai does. If your main complaint is rage you don't recognize or crying that comes out of nowhere, these particular studies don't speak to that.

There's no established dose for dong quai or chasteberry for PMS or PMDD symptoms in the research reviewed here. The chasteberry studies used a specific standardized extract, often called BNO 1095, not a plain dose you can read off a drugstore label and expect to match.

Supplement products vary widely in concentration and preparation. 'Natural' doesn't mean a dose can't be too high, too inconsistent, or interact with something else you're taking.

If you're thinking about trying either one:

1. Note any other medication you take, or a bleeding or liver condition, since both affect how safe a starting dose is for you.
2. Track your symptoms for at least one full cycle before you start, so you have something to compare against.
3. If you do try one, give it time and keep notes on any side effects, not just whether your mood changed.

Chasteberry is generally described elsewhere as causing mild side effects like nausea, headache and stomach upset, but the trials cited here measured breast pain and prolactin, not a full side-effect profile, so this picture is incomplete.

Dong quai's side effect profile is less tested in controlled trials. Reported issues with dong quai and related Angelica species include:

• Increased sensitivity to sunlight
• Stomach upset
• Headache
• Changes in bleeding, because dong quai contains coumarin-like compounds

None of this comes from a trial measuring PMS or PMDD outcomes. It's based on how the plant behaves pharmacologically, a different kind of evidence than a placebo-controlled study.

If you notice unusual bruising, heavier bleeding than normal, or a rash after sun exposure while taking dong quai, stop taking it.

Dong quai's coumarin-like compounds can increase the effect of blood thinners such as warfarin, raising bleeding risk. If you're on any anticoagulant, this is worth a conversation with a doctor before adding dong quai, not after.

Possible interactions to flag with a doctor include:

• Blood thinners (warfarin and similar medications)
• Hormonal contraceptives
• Fertility treatments that affect prolactin or dopamine
• Antidepressants, including SSRIs sometimes used for PMDD

Neither herb has been well studied in pregnancy or while breastfeeding, so most guidance is to avoid both there. If you're already on a prescribed PMDD treatment, mixing in an untested herbal supplement adds a variable your doctor can't account for without knowing about it.

This doesn't mean dong quai or chasteberry are unsafe to discuss with a doctor. The evidence just doesn't support picking either one specifically for premenstrual mood symptoms over options with a clearer track record.

Here's how some commonly tried non-drug options for PMS compare, based on the trial evidence described in these papers:

PMS treatment: what actually helps covers the options with stronger evidence behind them, including ones a doctor can prescribe. For more on how these studies were done, see PMS and PMDD research, summarised.