Excessive shedding of scalp hair. There are two forms of effluvium viz:

Anagen Effluvium & Telogen Effluvium

see also: Loose Anagen Syndrome

 

Hairshafts are produced by follicles within the skin in all but few locations viz: palms soles, lips, eyelids, backs of distal phalanges and parts of the external genitalia. Each productive hair follicle provides hairshafts throughout the life of the person. Some follicles may intermittently produce vellus or terminal hairshafts.

The repetitive three-phase 'hair cycle' - the process of follicle degeneration (with hairshaft eviction) and subsequent folliculo-regenesis (with hairshaft regenesis). The phases are termed: Anagen Catagen Telogen:

The Anagen Phase (folliculo-regenesis).
Folliculo-genesis and the rapid mitosis of cells by the dermal papilla creating the hairshaft and its surrounding anchoring membrane the epithelial sheath. Hairshaft growth rate is approximately 1-2 cm per month for terminal scalp hairs. At any given time approx. 80-85% of hair follicles will be in the Anagen phase.
The Anagen period will usually function for 2 -7 years (up to 10 years in certain instances). This variable period of ceaseless hairshaft production governs the ultimate length hairshafts may attain in any given person.

The Catagen Phase (mitosis ceases, the follicle commences a shut down).
All hair follicles enter periods of degeneration throughout the persons life. Approx. 3% of healthy follicles will be entering this shutting down phase (Catagen) at any given time. During this period the epithelial sheath shrinks to form a minute 'club root' attached to the hairshaft's proximal extreme. The hairshaft is thus prepared for eviction. The Catogen phase lasts approximately 10-20 days.

The Telogen Phase (follicle resting phase in which hairshafts are free to vacate).
Approximately 12 - 20 % of hair follicles are in the amitotic or resting (Telogen) phase at any given time. During Telogen the prepared hairshafts ('club hairs') vacate the follicle freely. The phase may last for up to 100 days (scalp follicles only) follicles producing eyebrows, eyelashes, and other body hair may take differing periods of time. Following the Telogen phase the follicles return to Anagen.

Exogen: The process of hair shedding. Whereas hairs may be shed at any stage of the cycle, the majority of shedding occurs during the 'new' Anagen phase.

The average scalp has 84000 - 145000 hair follicles. In healthy persons at any given time, approximately 80-90% of scalp follicles are in the hairshaft producing (Anagen) phase which may in extreme cases last for up to 10 years, with 10-20% in the telogen phase which lasts for approximately 100 days. 60-150 hairshafts vacate their follicle per day. In disease/distress the Anagen / Telogen ratios are subject to dramatic change.

The author has observed patients losing all but the shortest hairs within 2-4 weeks of the onset of either effluvium.

i) Anagen Effluvium

Anagen Effluvium: a significant loss of hairshafts in their Anagen phase. The onset may be rapid (e.g. Within 2-4 weeks of the cause). Major hair loss may result in extreme cases. Hair regrows spontaneously.

Causes:

• Chemotherapy drugs (antimitotic agents)
• Radiotherapy
• Malnutrition
• Seborrhoeic dermatitis and other localised dermatoses.
• Oral contraceptives
• Vitamin A poisoning
• Iron deficiency
• Chronic infections
• Some Drugs

 

ii) Telogen Effluvium

Telogen Effluvium was first described in 1961. It relates to a specific form of diffuse hair loss.


Telogen Effluvium - eviction of hairshafts from follicles which have prematurely entered their resting phase. This can produce excessive hair losses, and may be thus explained:
i)   Hair follicles prematurely terminate the Anagen (mitosis) phase.
ii)  The Catogen phase of the hair cycle is omitted.
iii) Hair follicles prematurely enter the Telogen (amitotic or resting phase).
iv) Hairshafts are lost in great numbers.
v)  Hair follicles return to Anagen and new hairshaft production ensues.

Hair losses in TE usually present within 6-12 weeks following stresses and other triggering factors. In many patients, the hair fall rates may be sufficient to reduce a previously wonderful head of hair to 1-2cm stubble within weeks. Lost hair usually regrows.

Causes:

•   Pyrexia (in particular a body temperature of 103.5 C).
•   Childbirth (rarely)
•   Severe infection (especially toxaemia)
•   Major surgery
•   Protein deficiency due to unsupervised crash diets.
•   Drugs including beta blockers, antidepressants.
•   Severe psychological stress

 

What can you do to help?

A reputable trichologist may be consulted. Is there a Society Registered Trichologist near you? (see CONSULTANTS)

 

© 2004 - B Stevens FTTS (Fellow of The Society)
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Orthodox Hair-sciences & Hair-specialisms - The Trichological Society