17 citations
,
  April 2016   in “Journal of Investigative Dermatology”    KB2115 (eprotirome) can safely extend the hair growth phase without damaging cells or changing hair color.  
     
           31 citations
,
  February 2019   in “International Journal of Cosmetic Science”    Caffeine applied to the scalp can protect hair follicles from UV damage.  
     
           15 citations
,
  July 2019   in “Journal of Investigative Dermatology”    CBD can either reduce inflammation and not affect hair growth at low levels or inhibit hair growth at high levels.  
     
           9 citations
,
  July 2020   in “Experimental Dermatology”    Topical L-thyroxine may help with wound healing and hair growth but should be used short-term due to potential risks.  
     
           3 citations
,
  November 2019   in “Journal of Investigative Dermatology”    Adenosine helps human hair grow and prevents hair loss by targeting specific cells.