Menopause: hot flushes and the honest evidence

Vasomotor symptoms — hot flushes and night sweats — are the main menopausal symptom, and the honest hierarchy is that hormone therapy is substantially more effective than any plant preparation.

Hormone replacement therapy reduces hot flushes by around 75% in trials and is the most effective treatment. The risk-benefit discussion is genuinely nuanced and has been distorted in both directions since the Women's Health Initiative; the current position is that for most women under 60 or within 10 years of menopause, the benefits generally outweigh the risks, and it is a decision to make with a clinician. This handbook cannot make it, and it should not pretend a herb is equivalent.

Black cohosh has multiple randomised trials with inconsistent results; pooled analyses generally find a small effect over placebo, and several well-designed trials have found none. There are rare reports of liver injury. It may act centrally rather than through oestrogen, which is why the older "phytoestrogen" framing is probably wrong.

Soy isoflavones — the trials are heterogeneous, with a modest effect in some pooled analyses and none in others. The effect, where present, is small and much less than hormone therapy.

Red clover isoflavones — similar picture; small and inconsistent effects.

St John's wort has small trials for menopausal symptoms, with a modest effect. It interacts with a very long list of drugs, including tamoxifen, which is relevant in this population.

Vaginal symptoms — dryness, pain with sex, recurrent urinary infection — are not treated by any of the above and are treated effectively by topical vaginal oestrogen, which is safe in almost everyone and not equivalent to systemic hormone therapy. This is an underused and highly effective treatment.

Hot flush triggers that can be managed. Alcohol, caffeine, spicy food, hot drinks, and a hot environment. Layering clothing. Weight loss reduces symptoms. Cognitive behavioural therapy has randomised evidence for hot flushes and for sleep.

The frame that matters. A woman with severe vasomotor symptoms and a poor night's sleep for months is suffering a treatable condition. Offering her black cohosh is offering a coin-flip when there is a treatment with a 75% effect size. Name both.