“Background: Few studies have reported on the use of cannabinoid products to treat hair loss.

Aim: This article aims to reconcile cannabinoids’ impact on hair growth.

Method: A comprehensive and structured search was conducted in PubMed and Google Scholar on 23 June 2022.

Result: 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 (≥10 μM). 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 six 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 3-4 mg 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.

Conclusion: 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 phytocannabinoid adulterants.”

https://pubmed.ncbi.nlm.nih.gov/36181341/

https://onlinelibrary.wiley.com/doi/10.1111/jocd.15427