Chamomile for PMDD: does it work?

No study has tested chamomile specifically in people with PMDD. The research that exists looked at premenstrual syndrome (PMS), a milder and far more common pattern of symptoms, and found a modest benefit over placebo.

PMS and PMDD share some symptoms, but PMDD is a distinct diagnosis with its own criteria: at least five symptoms, one of them a mood symptom, confined mostly to the week before the period. PMDD, explained walks through how that diagnosis is made.

Because the trials were done in PMS, not PMDD, results can't be assumed to carry over directly. Based on the PMS data, chamomile looks safe and may ease emotional and physical discomfort, but it isn't a guideline treatment for PMDD and shouldn't replace one.

Six studies, mostly small randomized trials, plus one systematic review, have looked at chamomile for premenstrual symptoms. Most were done with university students in Iran, ran for one to two menstrual cycles, and compared chamomile capsules against a placebo or against mefenamic acid, a pain reliever.

None of these trials used the daily symptom tracking that a PMDD diagnosis requires, so the result is evidence for PMS, not PMDD. For the fuller picture on the milder condition, see chamomile for PMS, and for a broader rundown of what's been studied, see the PMS and PMDD research summary.

Since no trial has set a dosing protocol for PMDD, what follows comes from PMS and dysmenorrhea studies:

• 100 mg capsule, three times a day, from day 21 of the cycle until the period starts ([3], [5])
• 250 mg chamomile powder, three times a day, starting 7 days before the expected period ([2], [6])
• A chamomile and L-theanine beverage, taken daily for five days starting two days before the expected period, tested for menstrual pain rather than PMS ([4])

These aren't interchangeable doses, just what different research teams tried. If you want to see whether any of it is actually helping, track your symptoms daily with something like the DRSP chart so you're comparing real data across cycles, not relying on memory from the week before your period.

The PMS trials measured results after one full cycle of chamomile taken for about a week before the period, and the comparator trial extended that to two cycles before comparing final scores.

If you're trying chamomile for PMDD, give it at least two full cycles before deciding whether it helps. One cycle can be thrown off by a lot of things: a cold, a stressful week, a stretch of poor sleep.

Track your symptoms daily rather than judging from how the last few days felt. That's the only way to tell whether chamomile is doing anything, or whether what changed was something else entirely.

Chamomile is one of the milder herbal options, and the PMS trials reported no serious side effects.

Still, like any supplement, it isn't side-effect free:

• Mild stomach upset or nausea
• Drowsiness, especially at higher doses
• An allergic reaction, particularly if you're sensitive to ragweed, marigolds, chrysanthemums or daisies, since chamomile is in the same plant family
• Skin irritation if used topically

These are known side effects of chamomile supplements in general; the cited PMS trials did not report detailed adverse-event data.

Chamomile isn't right for everyone. Avoid it if you:

• Are pregnant, since chamomile isn't established as safe in pregnancy
• Take blood thinners like warfarin, since chamomile may add to their effect
• Have surgery coming up, for the same reason
• Are allergic to ragweed, marigolds or other plants in the daisy family

These same cautions apply to most herbal supplements taken near your period, not just chamomile. Mention it to any doctor you see, alongside anything else you're taking.

PMDD guidelines point to a short list of treatments with real evidence behind them: SSRIs (which some people take only in the two weeks before their period), certain hormonal contraceptives, and cognitive behavioral therapy. A doctor decides which combination fits your situation.

Chamomile can sit alongside these as a gentler add-on. It isn't a replacement for any of them. For the full list of what's recommended, see PMDD treatment: what actually helps, and if you want a clinician who already understands this diagnosis, finding a PMDD specialist is a good next step.

If you want help tracking whether chamomile is actually making a difference, Niyora is a PMS and PMDD support app that estimates your PMS window so you can compare how you feel against where you are in your cycle, no account needed.