Valerian for Hot Flashes: Dose Conflicts and What the Trial Tables Show

The selected trials tested root powder, a valerian capsule and a two-herb extract. Their dose descriptions and measured outcomes need separate examination.¹²³

The root-powder paper gives two capsule strengths

The 2013 study¹’s results section describes 76 women allocated equally to valerian or placebo, with 68 analyzed. Exclusions included missed doses, lack of benefit, recording problems, gastrointestinal symptoms, dizziness and other medication use. Removing participants for these reasons can affect the estimate of benefit.¹

Hot-flash severity favored valerian after treatment. However, the abstract says 255 mg per capsule; the methods say 225 mg, taken three times daily for eight weeks. The methods describe ground root placed into capsules. That inconsistency prevents a confident statement of the tested dose.¹

A second trial used 530 mg twice daily

The 2018 trial² enrolled 60 postmenopausal women aged 45–55. Its published abstract describes 530 mg valerian capsules twice daily for two months, compared with starch placebo.²

It reports lower severity with valerian at one and two months, and lower frequency at two months. The abstract provides significance tests but no numerical between-group difference in daily flash counts. Those results support a possible effect without showing readers how many fewer flashes to expect. The full paper was unavailable for this review.²

The fennel-valerian trial needs a closer table reading

The 2023 trial³ randomized 76 women and analyzed 70. It compared 500 mg capsules containing equal amounts of fennel and valerian extracts, twice daily for eight weeks, with starch placebo. It cannot isolate valerian’s contribution.³

Severity favored the mixture. Frequency fell in both groups, but the adjusted eight-week comparison was not statistically significant, P = 0.060. A separate analysis across measurement times favored treatment for frequency. The abstract’s favorable summary omits this distinction.³

Reported flash duration increased in both groups, without a significant final between-group difference. Shorter flashes were not demonstrated. The university funded the study; the authors reported no relevant conflicts.³

Check the ingredient list and medicines together

NCCIH says the evidence remains insufficient to know whether valerian helps menopause symptoms. Its safety guidance advises against combining valerian with alcohol or sedatives. Reported adverse effects include mental dullness, stomach upset and vivid dreams; very rare liver-injury reports often involved herbal combinations. Long-term safety is unknown, and withdrawal symptoms have followed abrupt stopping after chronic use.⁴

Bring the full label and medication list to a pharmacist or clinician, including anything taken for sleep. Ask whether the proposed product matches a studied formulation and whether its risks fit your medicines and medical history.

“The Supplement Shelf” in Chapter 5 of My Body Changed. Now What? explains why a change noticed while taking a supplement cannot establish how much the supplement contributed.