Hair loss/Hair Thinning/Alopecia

Hair loss of the scalp is of great concern to both men and women. It seems that eventual hair loss is almost inevitable.  By the age of 70, nearly 80% of men and 40% of women will have noticeably thinning hair.

Normal hair growth

There are approximately 100,000 hairs on the scalp.  Hair growth occurs in a cycle.  At any one time an individual hair is growing, resting or falling out.
The three stages of the hair growth cycle are:

  • Anagen – growing phase. 
    • Approximately 90-95% of hairs are in anagen phase at any given time.
    • Depending on your genes, this hair growth phase lasts from 3 to 10 years.
    • People with long anagen cycles can grow very long hair before it falls out.
  • Catagen – transition phase
    • A short transition phase between anagen and telogen
    • Less than 1% of hairs are in this phase at any given time.
    • The transition phase lasts about 3 weeks
  • Telogen – resting phase
    • 5-10% of hairs are in telogen resting phase.
    • The resting phase lasts 2-3 months.
    • At the end of telogen, a new anagen phase starts, and a new growing hair pushes the old hair out of the follicle
    • With this process it is normal to lose up to 100 hairs per day. 

Types of hair loss/alopecia

There are a large number of conditions that can cause hair loss or hair thinning.  Loss of up to half of scalp hair occurs before hair loss is noticeable on casual inspection.

A careful history and examination of the scalp must be performed to determine the following:

  • Is the hair loss scarring or non-scarring?
    • In areas of scarring hair loss, there is disappearance of the hair follicle openings, and the skin is smooth and shiny.
  • Is the hair loss happening throughout the scalp (diffuse alopecia) or is it patchy?
  • Is the hair coming out at the roots or breaking off?

Some conditions like fungal infections of the scalp (tinea capitis), lupus erythematosus and traction alopecia, can produce both scarring and non-scarring hair loss.

Types of hair loss/alopecia
We will cover some hair loss disorders in more detail on their individual pages.  Please follow the highlighted links.

  • Non-scarring hair loss
    • Diffuse
      • Androgenetic (female pattern, male pattern)
      • Telogen effluvium
        • Illness
        • Postpartum
        • Sudden weight loss
        • Medications
        • Toxins
      • Endocrine abnormalities
        • Hypothyroidism
        • Hyperthyroidism
        • PCOS
      • Alopecia areata
      • Loose anagen syndrome
    • Patchy
      • Tinea capitis (ringworm of the scalp)
      • Alopecia areata
      • Trichotillomania
      • Syphilis
      • Traumatic (traction alopecia)
      • Loose anagen syndrom
  • Scarring hair loss
    • Tinea capitis (fungal infection of the scalp)
    • Traumatic (traction alopecia)
    • Tumors, benign or malignant
    • Skin diseases, such as sarcoid or scleroderma
    • Lymphocytic
      • Central centrifugal scarring alopecia
        • Formerly called “hot comb alopecia” or “follicular degeneration syndrome”
      • Discoid lupus
      • Lichen planopilaris
        • Frontal fibrosing alopecia
      • Pseudopelade of Brocq
    • Neutrophilic
      • Folliculitis decalvans
      • Dissecting cellulitis
    • Mixed
      • Acne keloidalis
      • Acne necrotica
      • Erosive pustular dermatosis

Diagnosis of alopecia

Diagnosis of alopecia requires a detailed history and physical examination.  For some forms of alopecia further work-up is required.

Both scarring and non-scarring forms of hair loss may require a skin biopsy to obtain a more accurate diagnosis.

Laboratory work-up of non-scarring alopecia includes:

  • Complete blood cell count
  • Iron studies, including iron, TIBC and ferritin
  • VDRL
  • Thyroid screening
  • Microscopic examination of hair
  • Possible fungal culture
  • Additional diagnostic methods may be necessary
    • Scalp biopsy
    • Antinuclear antibodies
    • Hormones
    • Heavy metal screens
    • Borate and thallium levels


  • John C. Hall Sauer’s Manual of Skin Diseases, 10th ed. Phila, PA. LWW publishers
  • Norwood OT, Lehr B. Female androgenetic alopecia: a separate entity. Dermatol Surg 2000;26(7):679-82
  • Nickoloff BJ, Nestle FO. Alopecia areata. Dermatologic Immunity. Curr Dir Autoimmun 2008;10:280-312
  • Whiting, DA. Male pattern hair loss: current understanding. Int J Dermatol 1998;37:561-66
  • Bouhanna P. Multifactorial classification of male and female androgenetic alopecia. Dermatol Surg 2000;26(6):555-561
  • Ross EK et al. Update on primary cicatricial alopecias. JAAD 2005;53:1-37
  • Olsen EA. Central centrifugal cicatricial alopecia. Dermatologic Therapy 2008;21:268-278
  • Hordinksy M. Cicatricial alopecia: discoid lupus erythematosus. Dermatologic Therapy 2008;21:45-48

Summit Medical Group is proud to provide medical, surgical and cosmetic dermatology services to women and men in the Tri-State Area, New York and New Jersey, including the following counties and cities: Essex County, Morris County, Bergen County, Union County, Passaic County, Somerset County and Sussex County, NJ - Livingston, Millburn, Short Hills, West Orange, Berkley Heights, Caldwell, Cedar Grove, Cedar Knolls, Chatham, East Hanover, Englewood Cliffs, Essex Fells, Fair Lawn, Florham Park, Fort Lee, Glen Ridge, Jersey City, Kinnelon, Madison, Maplewood, Mendham, Montclair, Montvale, Morristown, New Providence, North Caldwell, Parsippany, Randolph, Roseland, South Orange, Springfield, Summit, Union, Verona, West Caldwell, Whippany and Westfield, NJ.


Hair loss/Hair Thinning/Alopecia
Real Self

A Member of the ASLMS
© Copyright 2012 - Summit Medical Group - All rights reserved :  Privacy Policies & Disclaimers  :  Site Map

Disclaimer: The information on this Web site is solely for to educate patients. It is not intended to be medical advice and, therefore, should not be considered a substitute for consultation with a qualified medical professional. Communications to or from the Summit Medical Group Web site and any person will not be used to establish a relationship between a patient and doctor.