An interesting new paper from March 2022 discusses the current status of palmar hyperhidrosis treatments. I liked the part titled emerging treatments for palmar hyperhidrosis (PH).
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8901220/
Radiofrequency stimulation: A recent study performed by Lin et al in 2017 used pulsed radiofrequency stimulation at the T2 sympathetic trunk in rats. A significant reduction in palm humidity of the treated side was observed in rats who underwent treatment. As a result, radiofrequency stimulation represents a potential reversible treatment option for PH, which may reduce the potential for permanent compensatory sweating. Further research, including clinical trials, is necessary to elucidate the efficacy of this treatment option in humans.
Ultrasound stellate ganglion block: A case report published in 2018 investigated a noninvasive ultrasound stellate ganglion block as another potential treatment for PH. This technique uses ultrasound to block the stellate ganglion, a sympathetic nerve ganglion located caudal to the sternocleidomastoid muscle, under local anesthetic. The procedure, which was performed for one minute per day on alternating sides, led to effective results as confirmed by a Minor’s starch test, without the noted side effects seen in similar surgical procedures.
Botulinum toxin type A (BoNTA) coated microneedles: The use of microneedles coated with BoNTA is a novel and exciting procedure that may lead to positive results in treating PH. A study published by Shim et al in 2019 outlined a design for BoNTA-coated microneedles, and tested its use in the foot pad of mice in vivo, showing a significant reduction in the sweating response. While this method is a promising, and potentially less painful approach to treating PH, additional research is necessary to confirm its efficacy in humans.
Fractional CO2 laser-assisted BoNTA: Fractional CO2 laser-assisted BoNTA delivery is another newly emerging procedure in the treatment of PH. This procedure involves using an ablative fractional CO2 laser on the palm, then applying a topical BoNTA solution directly after, enabling transdermal BoNTA absorption. A study published in 2021, which performed fractional CO2 with 30 primary PH patients, showed clinical equivalency between this procedure, utilizing 75 units topically of BoNTA, and 50 units of injected BoNTA for the treatment of PH, with similar lengths of effectiveness but a reduction in pain intensity. Despite its recent emergence, this technique has already demonstrated promising results.