Introduction, Structure of hair and Hair growth cycle

1. STRUCTURE OF HAIR
AND HAIR GROWTH
CYCLE
UNDER THE GUIDANCE OF
Kamal Deka
Assistant Professor
SUBMITTED BY
Debasish Deka
M.Pharm 2nd Sem
FACULTY OF PHARMACEUTICAL SCIENCE, ADTU

2. INTRODUCTION
 STRUCTURE OF HAIR
 HAIR GROWTH CYCLE
CONTENTS

3. Hair is made from strong structural protein
named as Kerotin. This is of exactly the same
protein from which the nail and outer skin layer is
comprised.
INTRODUCTION:

4. There are mainly 3 glands are involve in hair.
 The epidermis is known as hair shaft. The hair shaft is
comprised of three layers: cuticle, cortex and medulla.
• The innermost layer (known as the medulla) only present
in large thick hairs
• The middle layer ( known as the cortex) which gives the
hair its strength, texture and colour.
• The outermost layer ( known as the cuticle) a thin and
colourless layer that is defensively to prevent damage to
the hair’s inner structure and to control water content of
hair fibre.
STRUCTURE OF HAIR

5.  The dermal papilla contains the blood supply and nerves
that produce nutrient for the hair. These vital nutrients
are needes in order for hair to grow. The dermal papila is
shaped smilar to a cone and sits inside the hair bulb.

6.  The oil glands of the skin are called sebaceous glands.
These glands are connected to the hair follicle and
secret sebum, an oily substance that lubricates the hair.
Structure of Hair

7. HAIR GROWTH CYCLE
Hair growth cycle comprises of 4 phases. These are
HAIR
GROWTH
CYCLE
Anagen
Catagen
Talogen
Exogen

8. 1) Anagen phase (Growing phase) -
The growing phase last 2-7 years and determine the
length of hair.
Hair grows arround half an inch a month and faster in
summer than winter. The anagen phase last and average
of 3-5 years, a full length hair averages 18-30 inches.
The anagen phase is generally longer in asian and last as
much as 7 years with hair being able to grow to one
meter.

9. 2) Catagen ( Transition phase)-
 This is the transitional phase that last about 10 days.
 The hair folecule shrink and detouches from the dermal
capillla.

10. 3) Talogen phase (Resting phase)-
 This is the resting phase which are less around 3 month.
Arround 10- 15 % of hair are in this phase.
 The old hair is resting, a new hair begins the growth
phase.
 Lastly hair enters the alogen phase, hair is release and
false out.

11. The follicle that remain inactive for 3 months the whole
process is repeated.
During the talogen phase the follicle remains dorement
for 1- 4 months.
Each hair follicle is independent and grows through the
growth cycle at different times, otherwisw all hair will
fall out at once. During the talogen phase the follicle
remains dorement for 1-4 months. 1-50 % of the hair are
in this phase growth at any event time.
At some point the follicle begin to grow again, softening
the ancure point and hair base will break free from the
root and the hair will be shed. Within 2 weeks new hair
shaft will begin to emarge once the tallogen phase is
complete.

12. 4) Exogen phase-
This is the part of resting phase where the old hair falls
and new hair continueous to grow. The thickness, texture
and shape of the hair is determine in this stage.

13. The following factors create an interruption of the normal
cycle causing excessive hair loss:-
 Stress
 Change in diet
 Drugs
 Illness
 Post pregnancy

14. THANK YOU