Primary focal hyperhidrosis affects approximately one to three percent of the population and substantially impairs quality of life, yet pharmacological options remain narrow. Every approved systemic and topical agent acts on the same cholinergic axis, blocking acetylcholine signaling at the muscarinic receptor of the eccrine sweat gland. This convergence on a single mechanism leaves an obvious question open: are there receptors downstream of the muscarinic step that, when blocked, would suppress pathological sweating without abolishing the cholinergic signaling on which the rest of the parasympathetic system depends? We propose that the transient receptor potential vanilloid 4 (TRPV4) channel is such a target. TRPV4 is expressed in human eccrine sweat glands, mediates calcium signaling downstream of cholinergic activation in mammalian sweat epithelium, and appears not to be required for ordinary thermoregulatory sweating. Selective TRPV4 antagonists already exist as research tool compounds and as a discontinued clinical candidate, GSK2798745, which has cleared first-in-human safety studies. We outline a stepwise experimental program that could test this hypothesis at modest cost using commercially available tool compounds, well before any clinical commitment is required.
Elijah Shorette (Mon,) studied this question.