Stellate ganglion block for treating hot flashes: a viable treatment option or sham procedure?

Stellate ganglion block (SGB) has been used for over 70 years to treat various cervical pain syndromes. Over the past 8 years, 4 different groups have reported on SGB's effects on hot flashes from unblinded, open-label trials. Review of these studies has shown markedly disparate results in terms of the magnitude of hot flash reduction from Baseline with one trial showing a 90% reduction in hot flashes and 3 other trials showing 28-44% reductions in hot flashes. The inconsistencies in these results in addition to the known potentially large (>50%) placebo effects that can occur in randomized controlled hot flash clinical trials make it difficult to render any conclusions regarding the efficacy of SGB for hot flashes at this time. A randomized controlled trial, including a sham saline treatment arm, needs to be performed to properly assess SGB's effects on hot flashes, Methodological challenges with such a study design are addressed and several suggestions are proposed to manage these challenges.