TLDR Certain drugs can cause early hair growth in mice by affecting the nerves.
In the 1999 study, researchers found that adrenergic drugs, specifically guanethidine and 6-hydroxydopamine (6-OHDA), induced premature hair growth in C57BL/6 mice. Over 80% of guanethidine-treated mice and about 65% of 6-OHDA-treated mice exhibited premature skin darkening and hair growth by day 20 post-treatment, while less than one-third of control animals showed these changes. Histological analysis confirmed mature anagen VI hair follicles in treated areas. The study did not observe similar effects with the B2-adrenoreceptor agonist isoproterenol. These results suggest that sympathetic nerves significantly influence hair growth and that manipulating these nerves could be a potential therapeutic approach for hair growth disorders.
101 citations,
January 1997 in “Journal of Investigative Dermatology Symposium Proceedings” Nerves and chemicals in the body can affect hair growth and loss.
86 citations,
January 1996 in “Clinics in dermatology” Hair can be damaged by daily routines, but protein-based products can protect and improve it.
124 citations,
August 1994 in “Journal of Investigative Dermatology” Dexamethasone speeds up hair loss in mice, while cyclosporin A slows it down.
33 citations,
August 1973 in “American Heart Journal” Propranolol can cause reversible hair loss.
21 citations,
May 2022 in “Frontiers in Cell and Developmental Biology” Hair growth and health are influenced by factors like age, environment, and nutrition, and are controlled by various molecular pathways. Red light can promote hair growth, and understanding these processes can help treat hair-related diseases.
21 citations,
May 2016 in “Experimental and Therapeutic Medicine” 
April 2016 in “Journal of Investigative Dermatology” Wnt ligands, produced by dermal papilla cells, are essential for adult hair growth and regeneration.
