Researchers reviewed four studies involving more than 160 participants in total and did not find a clear, consistent effect. In three of the four studies, any improvements compared with placebo were minimal, according to Medical Xpress’s report on the presentation. That is a long way from the kind of result that changes practice on enthusiasm alone.
The most eye-catching number came from a small single-arm study included in the review, where daily hot flash frequency dropped by as much as 69% at the maximum nitroglycerin dose. Symptoms returned after treatment stopped. Headaches were the most common adverse event, affecting up to two-thirds of participants early in treatment.
That leaves the treatment in a narrow but familiar lane: potentially useful, thinly evidenced, and still awkward around side effects. Hormone therapy remains the most effective treatment for moderate-to-severe hot flashes, but not every woman can or wants to use it. The demand for nonhormonal options is real; the data here are simply not sturdy yet.
Dr. Flavia Fairbanks Ruano of the University of Miami Miller School of Medicine, the lead author, said the findings suggest transdermal nitroglycerin is an interesting possible nonhormonal approach, while stressing that the evidence is still limited. Dr. Stephanie Faubion, medical director for The Menopause Society, similarly described the approach as potentially promising but said larger, well-designed studies are needed before its role in clinical practice can be determined.
The review’s own conclusion is restrained in the right way: modest reductions may be possible, especially for postmenopausal women with contraindications to hormone therapy, but the evidence is limited, imprecise and inconsistent.
Isla Camilleri 
Ryan C