63 citations,
May 2000 in “Australasian Journal of Dermatology” Chemotherapy and bone marrow transplant can cause permanent hair loss.
23 citations,
December 2001 in “Lasers in Surgery and Medicine” Permanent hair removal is hard, but using longer laser pulses at lower power might improve results.
8 citations,
April 2013 in “Journal of The American Academy of Dermatology” Some breast cancer patients treated with high-dose docetaxel may experience permanent hair loss.
1 citations,
January 1967 in “The BMJ” The document concludes that while some hair and scalp disorders can be treated, hair loss from destroyed follicles is permanent, and damaged hair can only regrow naturally.
58 citations,
October 2001 in “Dermatologic Clinics” Hair loss can indicate underlying systemic diseases and addressing these can sometimes reverse the hair loss.