Hair Loss

What is normal hair growth?

The scalp hair grows about one centimeter per month. It’s growth cycle is divided into 3 phases.

  • Growing phase (Anagen) lasts for 2 to 6 years
  • Stage of partial degeneration (Catagen) lasts for 10 to 14 days
  • Resting phase (Telogen) lasts for 2 to 3 months whereby the hair drops subsequently

About 90% of the hair on the scalp is in the growing phase. About 10% is in the resting phase. The average life span of a hair is about five years.  

How many hairs are normally shed every day?

Everyday some of the hair is being shed as part of the cycle. Up to a hundred strands of hair can be shed in one day.


What can cause excessive or abnormal hair loss?

Excessive hair loss or baldness (Alopecia) may occur:

  • After a stressful condition such as :
    • Serious illness
    • Major surgery
    • After giving birth

Hair stops growing and goes into a resting phase (Telogen effluvium) about 3 to 4 months following the above stressful episodes.

  • As a result of hormonal problems
    • Thyroid diseases
  • Due to underlying diseases such as Systemic Lupus Erythematoses (SLE)
  • As a side-effect of certain medicines e.g.:
    • Anticoagulants (Warfarin)
    • Medicine used to treat cancer (Chemotherapy)
    • Birth control pills (Oral contraception)
    • Antidepressants
  • In Androgenic Alopecia
    • Male-pattern baldness:
      • Is an inherited condition common in men
      • Can occur as early as in the 20’s
      • Starts with receding of the hair line in front and on top of the head
    • Female-pattern baldness:
      • Occurs in genetically predisposed women
      • Generalized thinning over the entire scalp, more marked on the top of the head
  • Other causes of excessive hair loss are:
    • Infections – fungal infections, commonly seen in childrenk
      • Patchy hair loss occurs
  • Alopecia aerate – auto immune disease where the hair follicles are destroyed by the patient’s own cells
    • It can occur as patches of bald areas
    • It can cause baldness of the entire scalp (Alopecia totalize)
    • It can affect the entire scalp, eyebrows, underarms and pubic hair (Alopecia universalis)
  • Psychological disorder with impulsive pulling of hairs (Trichotillomania)
    • It usually affects girls more than boys
    • It is associated with depression


What should I do if I have excessive or abnormal hair loss?

You should consult a doctor for advice and treatment.

  • If the hair loss is due to stress, do not worry because it is temporary and the hair will re-grow
  • Investigations to rule out other diseases such as thyroid diseases and SLE may be required and would need to be treated accordingly
  • Fungal infection is treated with antifungal medicines
  • Medications may be helpful in some instances
    • Topical minoxidil 2% and 5% may help slow or prevent male and female pattern baldness
    • Finasteride tablets can be used for male-pattern baldness
  • Psychological therapy is required for treatment of Trichotillomania


Last Reviewed : 27 April 2012
Content Writer : Dr. Sorya A. Aziz
Reviewer : Dr. Hargeet Kaur a/p BAsant Singh