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Male pattern hair loss , otherwise known as androgenetic alopecia, is an issue that has been a concern to many men.
Cycles of hair growth
In a normal healthy head of hair, the follicles on our scalp can be in three phases.
The anagen phase is known as the growth phase.
About 80% of our hair should be in this phase and it lasts a good 3-5 years. The hair is receiving good nourishment from our blood circulation and is constantly growing.
The catagen phase - otherwise known as the transition phase.
Only a small amount of hair is in this phase. This is a short 2 weeks transition stage where hair starts detaching from the follicles and blood supply. The growth of the hair stops.
The Telogen phase
About 20% of our hair is at this stage and it can last for about 2-3 months. This is the phase where the old hair drops off and new hair starts to grow.
From the telogen phase - the follicle will transit into the anagen phase again. Our hair follicles will move through these three phases repeatedly.
What causes androgenetic alopecia?
The male hormone that is responsible for causing hair loss is Testosterone.
Testosterone is converted into dihydrotestosterone by an enzyme called 5a-reductase within our body. Dihydrotestosterone ( DHT for short ) will bind to the hair follicles and cause :
- Accelerated conversion from anagen phase to telogen phase - meaning more hair fall and lesser hair growth
- Over time, it will also cause the hair follicles to shrink in size and as a result, the hair becomes thinner and finer
- Finally, the hair follicle will close up and stop producing hair.
The longer this process is allowed to continue - the more irreversible the condition becomes. So treatment has to start as soon as you notice increased hair thinning.
Who are at risk of male pattern hair loss?
Family history
If we have a close relative with male pattern hair loss, for example our uncle or father, then our risk of suffering from it is higher
Age plays a part
the older we get, the higher the chance.
Classifications of hair loss stages
There are different classifications to the stages of male pattern hair loss.
One that is commonly used is the Norwood Hamilton scale. We use this scale to help identify which stage our patient is at and it also shows the severity of the condition.
In stage 1, there is mild recession of the frontal hair line
From stage 4 onwards, there is balding seen at the top of the head ( an area we call the vertex )
At stage 6 and beyond, the frontal recession will meet with the vertex hair loss
Stage 7 is the worst where the patient will lose all his hair at the crown.
Treatment for hair loss
Topical application
The only proven topical application that helps will be minoxidil spray. The exact mechanism of Minoxidil is not determined yet but animal studies found that it could potentially shorten the dying phase of hair follicles and prolong the growth phase.
It has also been shown to increase the size of follicles.
It can potentially improve hair growth in men over 6 months following which they have to use it for the long run. It can occasionally cause temporary hair loss for the first 2-3 months and sometimes scalp irritation and itch.
Oral Medication
The Oral medication that we often prescribe is finasteride - the brand name is propecia. Propecia is only licensed for use in men.
What it does is that it blocks the conversion of testosterone into DHT and in doing so, prevents the premature thinning of hair and premature closure of follicles.
It is a very effective treatment but there are some side effects to taking this medication, so please have a detail consultation with your doctor.
Treatments
Some of the treatments that may be used in conjunction with minoxidil and propecia are :
a) Lasers
Firstly , low level laser therapy has been extensively studied. This low energy red or almost infra red light can be applied on the scalp daily and that has been proven to be a very safe method in stimulating hair growth.
In recent studies, there are also exploration into using semi ablative fractional lasers in the treatment of male pattern hair loss.
b) Hair transplantation
The most invasive treatment of all would be hair transplants. When all else fails, patients may wish to consider this surgical approach.
Newer methods of treatment that are being evaluated including
- PRP ( platelet rich plasma ) injections
- Engineered growth factors injections
These treatments are currently being studied and evaluated.
Conclusion
Having a full head of hair does wonders to the confidence of a man. Understand that male pattern hair loss is usually genetical and seek consultation and treatment as early as possible as treatment success depends on the early stage of diagnosis and intervention.
By : Dr Chen Yiming
Family Physician, MBBS (Singapore), GDFM (NUS), GDFP Dermatology (NUS)