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Q: I have been reading various articles and forum postings and it would seem that a person utilizing Propecia might experience increased “shedding” of hairs (outside of the normal hair cycle) around the 12 week mark after a hair transplant and lasting around 2-4 weeks. The forum postings suggest that one will not only see the miniaturized hairs being lost, but also normal terminal hair in greater than expected levels. Does an explanation exist to explain this increase in shedding hairs? — B.T., Manhattan, NY

A: Our understanding is that finasteride only affects miniaturized hairs — i.e. hair affected by DHT — and that this is all that should be shed. Remember, however, that much of the thinning a bald person experiences is due to thousands of partially miniaturized hair, and these can look very much like a full terminal hair in its early stages.

See our page on Shedding After A Hair Transplant.

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Q: What does the hair transplantation process do to your existing hair? — R.V., London, UK

A: When we perform hair transplant surgery, we transplant into an area that is either bald or has some existing hair. The hair that is existing is undergoing a process called miniaturization. What this means is that the hairs are continuing to decrease in size – both in diameter and in length. When we perform a hair transplant, we don’t transplant around the existing miniaturized hair on your scalp, we transplant through it. And the reason why we do that is because the miniaturized hair, the fine hair that is being affected by DHT, is eventually going to disappear, so you don’t want there to be any gaps.

So the question is, does the hair transplant actually destroy the existing hair? The answer is that it doesn’t destroy, but it can “shock” it. In other words, creating recipient sites (that the grafts are placed into) will temporarily alter the local circulation of the scalp and this can cause some of the hair in the area to be shed. The reason why hair may be shed is that hair is naturally cyclical. In other words, hair is normally growing, shedding, and then regrowing again. When you stress the scalp, the growing hair may be shed prematurely, but then it regrows.

If you think about the process of electrolysis, it makes sense that you don’t damage follicles from making recipient sites during a hair transplant procedure. In electrolysis used to treat unwanted hair, you stick a needle in the follicle, and you turn on an electric current. And you burn it. And then what happens to the hair? It usually comes back and you need to do it a few more times, even though we are applying an electric current via a needle placed directly in the follicle. So it makes sense that by just inserting a fine needle – the tool commonly used to make a hair transplant site – into the skin, one would not destroy hair follicles. However, the cumulative effect of making hundreds or thousands of recipient sites does shock the follicles and, as a result, some may shed their hair.

It can occur with general anesthesia – when the scalp is not even touched – and it can occur with oral medications, from pregnancy, or after psychological stress. So if you have hair restoration surgery and there is shedding, and it takes six months to a year for the transplanted hair to grow in, during this time hair transplant patient will experience some thinning. Since miniaturized hair is going to eventually disappear anyway, some of the miniaturized hair that is shed may not return. But if it is healthy hair, and it is shed, it will grow back. And, of course, the transplanted hair will be growing in as well during this time.

I am often asked to describe how much can be expected to be shed. The answer is that it is an amount that is often noticeable by the patient, but not noticeable by anyone else.

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Q: After my hair transplant procedure I had some shock loss, and then after about 4 1/2 to 7 months I had tremendous growth — really thick. I was amazed actually. Now, at 8 months it has thinned again, quite a lot compared to the growth I had before. I just wondered if this was a normal growth pattern and whether further growth could be expected? — N.T., Brooklyn, NY

A: This is not the most common situation, but should not be a cause for concern. The newly transplanted hairs are initially synchronous when they first grow in — i.e. they tend to all grow in around the same time (with some variability). This is in contrast to normal hair, where every hair is on its own independent cycle. Sometimes the newly transplanted hair will shed at one time before the cycles of each hair become more varied asynchronous.

For continued discussion of this topic, visit our page on hair growth and the growth cycle. Or read posts in the topic of Growth after a Hair Transplant.

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Q: What are the possible obstacles that you see with hair cloning using the plucking technique? — D.E., Boston, MA

A: Plucked hair does not contain that much epithelial tissue, so we do not yet know what the success of the procedure will be. Plucked hairs will most likely grow into individual hair follicles that are not follicular units and therefore, will not have completely the natural (full) look of two and three hair grafts. This limitation may be circumvented, however, by placing several hairs in one recipient site. It is possible that the sebaceous gland may not fully develop, so the cloned hair may not have the full luster of a transplanted hair.

The most important concern is that, since the follicle is made, in part, by recipient cells that may be androgen sensitive, the plucked hair derived follicles may not be permanent. It is possible, that since all the components of a normal hair may not be present, the cloned hair may only survive for one hair cycle.

Since the ACell extracellular matrix is derived from porcine (pig) tissue, the procedure may not be appropriate if you are Kosher or allergic to pork. Of course, we do not know what other obstacles may arise since this technique is so new –- or even if the ones mentioned above will really be obstacles at all -– only time will tell.

Follow the latest in Hair Cloning Research

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Q: I started thinning and saw more hair in the tub. I began Rogaine and stopped shampooing every night and is seems that there is now more coming out every time I shower. What is going on? — E.U., Short Hills, NJ

A: Rogaine can cause shedding at the beginning of treatment (i.e. in the first 3 months) but this is expected as it causes some hair to begin a new cycle of shedding and re-growth. This means the medication is working.

Another reason for your apparent shedding is that the less you wash your hair, the more will be lost each time. Go back to shampooing every day and see what happens.

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Q: I had my first hair transplant of 1100 grafts five months ago. The hair has been growing in well and I am very satisfied with the progress, but the new growth appears to occur in different cycles. Some of the hair never fell out and started growing within weeks. At around three months, a lot more started to grow, and now there seems to be even more growth of new hair coming in its finer stages. Is it normal for transplanted hair to begin growing at different times? Why does some hair come in looking thick and other hair start off finer and then gradually thicken up? — E.R., Bushwick, N.Y.

A: You are describing accurately how hair grows after a hair transplant. After the hair restoration procedure, the transplanted stubble is shed and the hair goes into a dormant phase. Several months later, growth begins as fine, vellus hair that thickens over time. The hair usually does not have its original thickness right away.

Typically, growth occurs in waves so that initially some areas will have more hair than others. Over the course of a year the cycles will even out and the hair will thicken to its final diameter.

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Q: I am 26 and I have been diagnosed with Diffuse Unpatterned Alopecia (DUPA) and realize I am not a candidate for hair transplants. I have been on Propecia for about 9 months. There have been periods of increased shedding throughout and I am still shedding what seem to be mostly very fine, miniaturized hairs. Do you think this is the Propecia speeding up the hair cycle and pushing out the old fine hairs, or do you think this is an increase in the pace of my genetic balding? I know that your post states that the accelerated hair loss generally stops by the 6th month. Does DUPA have any effect on the timeframe? Also, I have read that Propecia is only effective for about 50% of patients with DUPA. Do you find that to be true, or have you found a different experience? — T.T., White Plains, N.Y.

A: It is hard to tell at 9 months whether it is shedding from the finasteride or that the medication is just not working. Since there is no way to tell, I would stay on the medication for 2 years for any possible shedding from the medication to have passed and to see if your hair loss actually stops.

Since the natural history of DUPA is so unpredictable, I would give it the full two years rather than the 1-year trial the company recommends. There is no real scientific data to support this recommendation, however.

Please take heart in the fact that people with DUPA often look great (even without any hair transplants) if they keep their hair very short, since they never develop that cosmetically unappealing wreath of hair around the back and sides that is normally associated with extensive balding.

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Q: Are there any side effects to the laser comb?

A: There can be an early temporary hair shedding in some patients. This is felt to be due to an acceleration of the hair cycle and is probably a mechanism similar to the one that causes early shedding when using Rogaine (Minoxidil) or Propecia (Finasteride).

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Hair transplant surgeon Robert M. Bernstein M.D. was recently interviewed on the National Public Radio program The People’s Pharmacy. Invited to speak about hair loss, Dr. Bernstein offered insights about the causes of hereditary baldness and it’s solutions, including hair transplantation.

The show was entitled “Dealing with Hair Loss” and addressed issues such as the importance of hair to our sense of well being.

The full hour radio interview was filled with informative facts about male pattern baldness, cultural attitudes toward hair loss and surgical hair restoration. For example, Dr. Bernstein was asked about his pioneering work in follicular unit hair transplantation and host of other questions ranging from the causes of hair loss to the psychological effects of balding. Here is one exchange from the interview:

Moderator: How one can tell the difference between hair loss from hormonal imbalances and common baldness?

Dr. Bernstein: Measuring hormone levels alone, although important for medical management, does not necessarily reveal whether the cause of the hair loss is actually hormone related or is genetic. The diagnosis is made by examining the scalp and looking at the hair under close magnification using an instrument called a “Densitometer.” If the hair shafts are of different calibers, this is relatively diagnostic of female patterned genetic hair loss and in this case hormone levels are often normal. Hormonal changes or imbalances, on the other hand, may cause alterations in hair texture (such as in thyroid disease) or a generalized shedding that can occur after childbirth (called telogen effluvium). In telogen effluvium, the hair can l actually fall out in clumps – you can literally get handfuls of hair, but the hair often returns over time. In genetic hair loss, however, it is not a question of the hair falling out any faster, but the hair being replaced with thinner, finer hair in each hair cycle, until the hair gradually disappears.

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Q: What is “shock fall out”? – D.B., Chappaqua, N.Y.

A: Shedding after a hair transplant is also referred to by the very ominous sounding term “shock fall out.” The correct medical term is “effluvium” which literally means shedding. It is usually the miniaturized hair (i.e. the hair that is at the end of its lifespan due to genetic balding) that is most likely to be shed. Less likely, some healthy hair will be shed, but this should re-grow.

Interestingly, if transplants are spaced less than one year apart, one often notices some shedding of the hair from the first transplant, but this hair grows back completely. For most patients, effluvium is not a major issue and should not be a cause for concern.

Typically, when shedding occurs, a patient looks a little thinner during the several month period following the transplant, before the transplanted hair has started to grow. The thinning is often more noticeable to the patient than to others. Shedding is generally noted as a thinning, rather than of “masses of hair falling out,” as the term “shock fall out” erroneously suggests.

In general, the more miniaturization one has and the more rapid the hair loss, the more likely shedding will be from the hair restoration surgery. Young, actively balding patients would be at the greatest risk. Older patients with stable hair loss would have the least risk. In either situation, since miniaturized hair is eventually going to be lost, the effluvium has no long-term effect on the outcome of the procedure.

It is important to differentiate the phenomena described above from shedding of the hair in the graft. This shedding is an almost universal characteristic of a hair transplant and occurs because during a hair transplant a graft is temporarily stripped of its blood supply. As a response to this insult, the graft sheds its hair. This shedding is generally noted beginning a week following the procedure and can continue for up to six weeks. A very small percentage of patients do not shed and the transplanted hair continues to grow. In others, the transplanted hair remains on the scalp for months until a new hair pushes it out. Whether a patient sheds or not has no bearing on the outcome of the hair restoration.

There are a number of ways to minimize the effects of post-operative shedding: the first is using medication, the second is timing the transplant properly, and the third is performing a procedure using a sufficient number of grafts.

• Medication

Finasteride 1mg reverses or halts the miniaturization process in many individuals and is thus the logical way to decrease the risk of shedding following a transplant. Although many physicians have had the clinical impression that this assumption is correct, there has been no controlled studies to date that prove this.

• Timing and the size of the transplant

It is important to wait until a patient is ready to have a transplant, and then to perform one of sufficient size so that if there is some shedding, the procedure will more than compensate for it – and thus be worthwhile. A problem that patients often run into is that they present to their doctor with early hair loss but with a significant amount of miniaturization. The doctor performs a small procedure and it does not even compensate either for potential shedding or for progression of the hair loss. The result is that the patient is thinner (or more bald) than he was before the procedure. The doctor rarely blames the problem on the fact that the procedure was too small or that the miniaturization was not taken into account, but only that the patient continued to bald. The better solution is to treat early hair loss with medication, but once you make a decision to begin surgery, have a procedure large enough to make a significant cosmetic improvement.

• Performing the procedure using a sufficient number of grafts

As a final point, it is a fallacy that some doctors’ techniques are so impeccable that they can avoid effluvium or those “small” procedures will avoid shedding. Of course, bad techniques and rough handling will maximize effluvium, but effluvium is what hair naturally does when the scalp is stressed and it is stressed during a transplant from the anesthetic mixture and the recipient site creation. It is important to note that it cannot be totally prevented. Despite claims to the contrary, Follicular Unit Extraction has no bearing on this process as it is a harvesting rather than a placing technique.

In sum, the best way to deal with effluvium is:

  • Treat with Finasteride — the active chemical in the hair loss drug Propecia — when hair loss is early
  • Perform a hair transplant only when indicated
  • Perform a hair transplant with skill and using a sufficient number of grafts
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Q: When a donor strip is taken out during a hair transplant and separated under the microscope, you can read on the internet that there is a wastage of grafts (about 15%), because of those unseen telogen hairs. What do you think about that and how does it affect the hair restoration? — T.B. Baldwin, New York

A: The Telogen phase of the hair cycle is about 3 months long and about 12% of follicles are in this phase at any one time. It is speculated that the follicles may be empty for perhaps 1/2 that time (this number may vary significantly between people). Therefore, approximately 6% of the hair follicles may be in telogen at any one time.

On average about 15% of the follicular units are 1-hair units (but this also may very greatly between patients). If 6% of all follicles are “empty” telogen follicles, then there should be .15 x .06 = .009 or about 1% of the patient’s 1-hair follicular units in the empty telogen phase that can’t be identified and will be missed on dissection.

The 1% isn’t very large. However, also consider that the remaining 5% of the empty follicles are associated with larger follicular units (i.e. those with 2-4 hairs). If these follicular unit grafts are closely trimmed, as is the practice with very dense packing, a much more significant number of follicles are at risk of being lost. With chubby follicular unit grafts (i.e., where the microscopic dissection leaves a protective sheath of tissue around the follicles) the risk should be closer to the 1%.

The lesson for hair transplantation is that over-trimming of grafts, for the sake of very dense packing, may waste telogen hairs as well as place the grafts at an unnecessary risk of mechanical trauma, drying and warming.

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Dr. Bernstein summarizes an article in the Journal of the National Cancer Institute:

Curis, Inc., a drug development company, has published data showing the effectiveness of a proprietary Hedgehog pathway activator to stimulate hair growth in adult mice. The study shows that a topically applied small molecule agonist of the Hedgehog signaling pathway can stimulate hair follicles to pass from the resting stage to the growth stage of the hair cycle. The Hedgehog agonist produces no other noticeable short or long-term changes in the skin of the mice.

This study also demonstrated that the Hedgehog agonist is active in human scalp in vitro as measured by Hedgehog pathway gene expression. The results suggest that topical application of a Hedgehog agonist could be effective in treating hair loss conditions, including male and female pattern genetic hair loss.

Preliminary results were presented at the American Academy of Dermatology (AAD) in February 2005. This work was based on a study in 2001 by Sato et. Al. who showed that the Sonic hedgehog gene is involved in the initiation of hair growth in mice.

Reference: Sato N., Leopold PL, Crystal, RG. Effect of Adenovirus-Mediated Expression of Sonic Hedgehog Gene on Hair Regrowth in Mice With Chemotherapy-Induced Alopecia. Journal of the National Cancer Institute, 2001, Vol. 93, No. 24.

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