Hair Loss/Haircycle

Advertisement


Question
QUESTION: Hi Dr Panagotacos,

How are you? Sir in male pattern baldness, as hair change their cycles like going from anagen to catagen phase then from catagen to telogen phase, now the hair follicles which have gone in resting phase (telogen phase) and have became dormant, so is it necessary to apply minoxidil on them in order to shift them back to anagen phase? Even if we do not apply minoxidil on those hair follicles,  so won't they shift back to their anagen phase on their own?  Provided one is inhibiting dihydrotestosterone with the use of propecia

ANSWER: Hairs normally go through the following cycles on their own-ANAGEN-> CATAGEN->TELOGEN--> and then back to ->ANAGEN-> etc -- all on their own..
However when there is an inherited Androgenetic Alopecia issue of inherited bald genes then the DHT starts to inhibit the future cycles and lowering that DHT level with Propecia allows for more of those hairs to recycle. Some of the weak hairs which still can not grow can be stimulated with minoxidil.
How many need minoxidil varies from patient to patient and the only way to know is to try it.

From Chapter 9  Chapter 9: Drugs That Grow Hair
http://www.hairdoc.com/hair-loss-answers/chapter-9-drugs-that-grow-hair/
Minoxidil seems to reduce the rate of hair follicle miniaturization, and can cause hair follicles that formerly produced full-size hairs, but have recently become miniaturized, to increase in size and begin to grow full size hairs again. Also, the enlarged follicles seem to remain in the anagen, or growth stage for a longer period. A longer growth period results in the production of longer hairs, and a look of more hair. Minoxidil acts as “life support” for hair follicles.

Results with minoxidil vary. For some people, it seems to have no effect at all. For others there is reduced rate of hair loss, but no visible new hair growth. Some men and women experience minimal new hair growth, but not enough to cover thin hair areas. Others enjoy dense new hair growth with areas that had previously been thin developing hair density similar to areas that were not affected by hair loss.


http://www.hairdoc.com/hair-loss-answers/chapter-2-normal-hair-growth/
Anagen Phase: The anagen phase is the “growing” phase of a hair follicle. It begins with a miniaturized hair follicle that may or may not have recently shed the hair it was growing during the previous growth cycle. At the beginning of the anagen phase, the hair follicle starts to grow back to full size and extend deeper into the skin. A new hair bulb is formed at the base of the follicle, and inside the hair bulb specialized dermal papilla cells begin to grow a new hair shaft. If the old hair has not been shed already, the new growing hair helps “push” the old hair out of the follicle. As the new hair grows out from the base of the follicle, it extends beyond the surface of the skin and appears as straight or curly, and with a color that can be blonde or brown or red or gray. Scalp hairs grow about one-half inch per month during the anagen phase, for a period of time typically ranging from four to six years. This is a rapid rate of cellular growth compared to most other tissues in the body.

Catagen Phase: Following the anagen phase, the hair stops growing and the hair follicle starts shrinking. This “regression” period is called the catagen phase. During the catagen phase the lower part of the hair follicle slowly disintegrates, and the hair follicle requires less nourishment from the blood supply. The structure of the hair bulb at the base of the follicle disappears, and the dermal papilla cells separate from the base of the follicle. The miniaturized hair follicle has a looser “grip” on the hair shaft, and normal body movement, grooming, or bathing may result in the hair shaft being shed at this time. The catagen phase for scalp hair follicles lasts about two to three weeks.

Telogen Phase: After the hair follicle has stopped shrinking, it enters the telogen or “resting” phase, which lasts for another three months, or so. During the telogen phase the follicle appears inactive, and the hair shaft may also be shed during this period. Shedding hairs are a normal part of the cycle of hair growth. Shed hairs may appear on bedding, on clothing, in combs and brushes, and many shed hairs simply go down the drain after shampooing. The point is that some hair loss every day is normal.

At the end of the telogen phase, the hair follicle enters the anagen phase again and begins to grow back to normal size. A new hair bulb is formed and a new hair shaft begins to grow, and the cycle of hair growth continues.

While many fur-bearing animals have hair follicles with synchronized growth and shedding phases, in humans the growth phase of hair follicles are not normally synchronized with their neighbors. This means that the hair follicles on people’s scalps are in different stages of growth, regression, or rest at any given time. But because the anagen (growth) phase lasts much longer than the other phases, the vast majority (ninety percent) of hair follicles on people are in some part of the growth phase, while only a small percentage are in the catagen (regression) or telogen (rest) phase. Growing hairs are not easily shed; however hair follicles in the catagen or telogen phase shed their hairs easily.

On average, young people with a full head of dark-colored hair have about 100,000 hair follicles on their scalp. Redheads often have slightly more than 100,000 scalp hair follicles, while blondes typically have fewer hair follicles. On average, about fifty to 100 hair follicles end the anagen phase each day, which is when the follicle begins to loosen its “grip” on the hair shaft, and the hair may be shed. Therefore shedding fifty to 100 hairs on any particular day is perfectly normal. Of course, about fifty to 100 hair follicles also re-enter the anagen phase each day, and begin growing new hairs as well, but this is less noticeable

---------- FOLLOW-UP ----------

QUESTION: 1) Sir , oral dht inhibitors such as Propecia and Avodart can completely halt genetic hairloss or is it such that these medicines can just slow down the hairloss and eventually person keep on losing his hair in his genetic pattern but at a slower rate?

2) Which medicine is more effective at halting/slowing down genetic hairloss, Oral dht blockers (such as Propecia / Avodart) OR minoxidil?

3) Only week hairs get addicted to minoxidl or even normal hairs get dependent on minoxidil?

ANSWER: Answers:
1)  Oral dht inhibitors such as Propecia and Avodart can completely halt genetic hairloss IN 85% of men and  does slow down the hairloss in the remaining 15%. In the few people where the loss doesn't stop and only slows down they keep on losing his hair but at a slower rate.

2)Oral dht blockers (such as Propecia / Avodart) are more effective at halting/slowing down genetic hairloss than minoxidil. Propecia stops hair loss in 85% of men and Avodart in over 90%.

3) All hairs get addicted to minoxidl since it is an artificial stimulant to hair growth it causes all hairs to grow thicker and longer and keeps them in the anagen phase for a longer time.

---------- FOLLOW-UP ----------

QUESTION: 1) Sir I am using 5% minoxidil for last 7 months for my AGA but now I am quitting minoxidil, so will I also lost my normal hairs after quitting minoxidil and then won't these hairs grow back by changing the cycle? Although I am regularly taking propecia for last 4 months and I m continuing propecia

2) Sir I tried 2 versions of minoxidil at the back of my hand,these are as follows
a) Product A = 1 ml contains 50mg minoxidil in a solution of alcohol 0.3g
b) Product B = 1 ml contains 50mg Minoxidil in a solution of alcohol 0.6ml and propylene glycol 0.2ml

Sir form both these products I am experiencing mild irritation and itching but no redness. So shall I use any of the above product on my scalp?
Also in your opinion from the above 2 products which one looks less irritating and would not cause any negative effect on my scalp and hair?

3) When you say that minoxidl since is an artificial stimulant to hair growth it causes all hairs to grow thicker and longer and keeps them in the anagen phase for a longer time. So if one discontinue minoxidil so the only thing would happen that instead of longer anagen , the anagen would just return to its original state? As it would have been without minoxidil

Answer
1. You will have to wait and find out. I have explained that not everyone responds the same way and that the hairs kept alive by minoxidil will fall out. I do not know which of your hairs have been kept alive by minoxidil but if it has only been 67 months there should not be much of a shed.
2. I've answered that question before. If the lotions bother you stop using them.
3. Since you have only used minoxidil for 7 months the worst that can happen is that you will look the way you did 7 months ago with an insignificant additional loss that would have happened in the interim 7 months.

Hair Loss

All Answers


Answers by Expert:


Ask Experts

Volunteer


Peter J. Panagotacos, <B>M.D.</B>

Expertise

I have 30 years experience in the field of medical and surgical Hair Restoration and am Board Certified in Dermatology and Hair Restoration Surgery.

Experience

I have 30 years experience in the field of medical and surgical Hair Restoration and am Board Certified in Dermatology and Hair Restoration Surgery. More information can be found at my website www.hairdoc.com

©2016 About.com. All rights reserved.