A cannabinoid Hairy-Tale: Hair loss or hair gain?

Abstract

Few studies have reported on the use of cannabinoid products to treat hair loss. This article aims to reconcile cannabinoids' impact on hair growth. A comprehensive and structured search was conducted in PubMed and Google Scholar on June 23, 2022. While cannabidiol (CBD), a phytocannabinoid, may cause hair growth, several other phytocannabinoids may lead to hair loss. Additionally, the effect of CBD on hair growth may be concentration-dependent. CBD may cause hair loss at high concentrations (≥10μM). Therefore, the concentration of CBD needs to be adjusted so that it is optimal for hair growth. One trial found that once-daily application of CBD-rich topical cannabis extract for 6 months increased nonvellus hair count by approximately 93.5% in 35 Caucasian AGA patients: 28 males aged 28-72 years [average 43 years] and 7 females aged 46-76 years [average 61 years]. Each application contained 3-4mg of CBD. The CBD-rich topical cannabis extract was prepared by ultra-pulverizing Cannabis sativa [hemp] flower into a green chalk-like powder [10.78% CBD and 0.21% tetrahydrocannabinol] and then infusing the powder into a lanolin paste and Emu oil carrier. Topical CBD preparations require further studies to establish their safety and efficacy profile. An ideal topical cannabinoid preparation should contain CBD at the right concentration and lack other phytocannabinoid adulterants.