Androgenetic Alopecia (AGA)

  • Pooya Khan Mohammad Beigi


Androgenetic alopecia (AGA) is the most common form of hair loss. It is characterized by the miniaturization of terminal hairs to thin vellus hairs and occurs due to androgen-dependent events. AGA is a hereditary condition, and although no permanent reversal exists, a number of therapies are available to slow and reverse the progression of hair loss. Males and females both suffer from AGA; however the distinct pattern of balding differs between the two [1].


Terminal hair Vellus hair Hereditary Polygenetic inheritance 5-alpha-reductase enzymes p450 alpha-aromatase enzymes DHT (5-alpha-dihydrotestosterone) 5-alpha-reductase Norwood-Hamilton classification system Terminal hairs Hair pull test Alopecia areata incognito Frontal fibrosing alopecia Trichoscopy Hereditary hypotrichosis complex Chemotherapy Aromatase inhibitor Myotonic dystrophy Steinert disease Myotonia Telogen effluvium Triangular alopecia Trichorhinophalangeal Minoxidil Skin irritation Hypertrichosis 5-alpha-reductase inhibitors Finasteride A type II 5-alpha-reductase inhibitor Dutasteride Prostate-specific antigen (PSA) Hair transplant Follicular unit transportation (FUT) 


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  • Pooya Khan Mohammad Beigi
    • 1
    • 2
    • 3
  1. 1.Department of Health ManagementNew York Medical CollegeValhallaUSA
  2. 2.University of British ColumbiaVancouverCanada
  3. 3.Misdiagnosis AssociationSeattleUSA

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