The FDA approval of oral finasteride, in the form of Propecia, has been a major breakthrough in the medical management of male pattern baldness. Before Propecia, the only medically proven treatment was topical minoxidil (Rogaine) and this medication was only minimally effective and, for many, a nuisance to apply. Propecia, on the other hand, is a once-a-day pill that can significantly alter the progression of genetic balding, particularly if started when the hair loss is still in its early stages.
The recent availability of finasteride in a generic, 5mg tablet, has decreased the cost of the drug – for those who don’t mind cutting up pills.
Avodart (dutasteride), a more potent medication that is related to finasteride, has been approved for the treatment of prostate enlargement, but not hair loss. Because of its affect on the balding process we will discuss this medication as well.
Rogaine, the brand name for minoxidil, was the first FDA approved medication for the treatment of hair loss. Rogaine is a topical solution that is applied directly to the scalp. Although originally a prescription drug, it can now be purchased over-the-counter in a generic form. It is sold in concentrations of 5% for men and 2% for women.
Rogaine was developed from the oral blood pressure medication minoxidil (Loniten). Minoxidil taken orally has potential serious side effects on the heart and circulatory system and is used only when other blood pressure medications have been unsuccessful. It was observed that patients who were taking minoxidil began growing body hair and it was reasoned that applying minoxidil directly to a bald scalp might cause hair to grow in this area as well – without producing the side effects of the oral medication. Studies showed that this was indeed the case, although the growth was generally modest.
The original studies on Rogaine were performed on the crown, so there is a misconception that it only works in this area. Although minoxidil usually works best in the crown, it also works to a lesser degree in other areas, such as the front of the scalp, as long as there is some fine (miniaturized) hair in the area. It will not work when the area is totally bald. The greatest benefit from the medication is seen from 5 months to 2 years. After this time there is a gradual decrease in effectiveness, so that those using minoxidil will continue to lose hair, but at a somewhat slower rate.
The exact mechanism by which minoxidil works is not known, but the drug is felt to increase the duration of the hair follicle growth cycle (called anagen). This improves the quality of the hair by increasing the diameter and length of fine, miniaturized hair. The simultaneous use of minoxidil and Propecia, which directly inhibits the formation of DHT, may have some synergistic benefit in the treatment of hair loss, although the latter medication is significantly more effective.
Minoxidil is most effective if applied to the scalp twice a day. The medication only works if it is in direct contact with the scalp (not the hair) and only works in areas where it is applied. Therefore, it is important to use the medication in the front part of the scalp if this is an area of thinning.
The 5% formulation is twice as effective as the 2% solution, but contains propylene glycol, a compound that can irritate the scalp and can make the hair feel sticky and difficult to manage. If this is a problem, one should consider using the 5% solution at bedtime and the 2% solution (which is alcohol based and less sticky) in the morning.
When using minoxidil, it may take 6-12 months before any results are seen. The majority of patients who see an effect from minoxidil experience a delay, or decrease, in the rate of hair loss. The drug also serves to thicken already existing hair, but most patients who do have results, grow only short, thin fuzz. It will not grow any new hair on a bald scalp.
Once a day topical use of Rogaine (topical minoxidil 2% and 5%) seems to be almost as effective as using it twice a day. The reason is that although minoxidil has a relatively short half-life of several hours when given orally, when topically applied, it has a half-life of 22 hours in the skin. This suggests that once a day dosing is a reasonable option. It is important to realize, however, that Pfizer, the company that now makes Rogaine, specifically states that it will be less effective if used only once a day.
If minoxidil is discontinued, the effects of the drug wear off within three months and the previous pattern of hair loss resumes. When minoxidil is restarted, one generally does not regain the hair that was lost, so it is best not to stop and start the mediation, but to use it regularly.
Minoxidil has been prescribed (off-label) in conjunction with other medications, such as topical retinoic acid (Retin-A), to enhance its penetration into the skin and thus increase its effectiveness. This combination of medications can increase the absorption of minoxidil into the bloodstream and may increase the risk of potential side effects, including changes in blood pressure and scalp irritation. It is important to use combination therapy under the supervision of a physician.
Only the 2% concentration of minoxidil has been approved for use in women. Female patients are generally more sensitive to the side effects of minoxidil in decreasing blood pressure (hypotension) and may get light-headed from the medication. Women also have an increased risk of developing allergic skin reactions (contact dermatitis).
An annoying local reaction that women sometimes get from topical minoxidil is the development of facial hair. Although the facial hair slowly resolves when the medication is discontinued, at times the hair may need to be removed. Carefully trying to avoid the medication dripping down onto the temples and forehead seems to reduce, but not totally prevent, this problem. There is a significantly greater incidence of these side effects if the 5% solution is used.
As we have discussed, male pattern baldness or androgenetic alopecia is caused by the effects of the male hormone dihydrotestosterone (DHT) on genetically susceptible hair follicles that are present mainly in the front, top, and crown of the scalp (rather than the back and sides). DHT causes hair loss by shortening the growth (anagen) phase of the hair cycle, causing a decreased size or miniaturization of the follicles. The effected hair becomes progressively shorter and finer until it eventually disappears.
DHT is formed by the action of the enzyme 5-alpha reductase on testosterone.
Finasteride is a drug that works by blocking the enzyme 5-alpha reductase Type II that converts testosterone to dihydrotestosterone (DHT) in the hair follicle. Propecia (finasteride) decreases both scalp and blood levels of DHT and its effect is felt to be related to both of these factors. Finasteride 1-mg/day decreases serum DHT levels by almost 70%. Although many think that finasteride lowers a man’s testosterone, the medication, on average, causes a rise in serum testosterone levels by 9%, although this is still within the range of normal.
It is commonly thought that finasteride was first conceived as a prostate medication and that, only by chance, was found to prevent hair loss. The fact is that in 1974, the researcher Imperato-McGinley and colleagues described a group of genetically male children from the village of Salinas in the Dominican Republic who were deficient in the enzyme 5-alpha reductase. These male children had very low levels of DHT and throughout their life, their prostates remained small and they did not develop male pattern hair loss or acne.
The objective of the scientists was to find a drug that could block the 5-alpha reductase enzyme and mimic the abnormality found in these men. They could then use this drug to prevent both prostate enlargement and hair loss. The decision was made, however, to obtain FDA approval for the medical indication first. In 1992, Finasteride 5-mg was released under the brand name Proscar, for use in men over 50 with prostate enlargement. In 1997, the FDA approved finasteride 1-mg/day (Propecia) for the treatment of male pattern baldness.
Finasteride is quite effective in the treatment of common genetic hair loss. Studies have shown that after five years of treatment, almost 50% of men treated with Propecia demonstrated an increase in hair growth and 90% at least maintained their hair over this time period. Only 10% were rated as having lost hair when compared to baseline. In men not on the medication, 75% were rated as having lost hair during the course of the study.
Propecia (Finasteride 1 mg) can hold on to hair at any age, but works best to re-grow hair in those who are younger. Occasionally we see patients in their 50s re-grow some hair with Propecia, but this is the exception rather than the rule. The benefits of finasteride will stop if the medication is discontinued. Over the 2-6 months following discontinuation of treatment with finasteride, the hair loss pattern will generally return to the state that it would have been if the medication had never been used.
Although it is often stated that “Propecia doesn’t work in the front”, the approved indication for Propecia does include the treatment of hair loss in the front part of the scalp. In our practice, we have seen many patients who have had early thinning in the frontal scalp and who have re-grown hair. The fact that DHT causes frontal hair loss and that Propecia blocks DHT gives a logical explanation for these effects. Of course, if there is no hair in the area at all, the medication is not going to work.
The absorption of Propecia is not affected by food, so one can take it any time during the day without regard to meals. Since finasteride takes up to a year or more to exert its full effects, in either re-growing hair or preventing further hair loss, patients must take finasteride for one year, or longer, before its effects can be accurately assessed. During the first six months, one may note some thinning of ones existing hair as the new growing hair replaces the miniaturized hair, so it is important to be patient during this period.
Side effects from finasteride at the 1-mg dose are uncommon, and fortunately reversible. Of men taking finasteride 1mg, 3.8% experienced some form of sexual dysfunction verses 2.1% in men treated with a placebo. The drug related side effects were just 1.5% greater than the controls and included decreased libido, erectile dysfunction, and decreased volume of ejaculate.
Most reported cases of sexual dysfunction occurred soon after starting the medication, but there have been reports of sexual dysfunction that have occurred at later points in time. The sexual side effects were reversed in all men who discontinued therapy, and even in 58% of those who continued treatment. After the medication was stopped, side effects generally disappeared within a few weeks.
For patients with sexual side effects it is recommended to stop the medication until the side effects go away and then restarting at a lower dose (either 1/4 or ½ of a 1-mg pill a day). If there are no side effects after several weeks on the lower dose, the patient can work up to the 1-mg per day dose. Even staying on a lower dose will offer some benefit. If side effects occur at the lower dose, one should abandon therapy with this medication.
When finasteride is discontinued, only the hair that had been gained or preserved by the medication is lost. In effect, the patient returns to the level of balding where he would have been had he never used the drug in the first place.
Rare adverse reactions included breast tenderness or breast enlargement (gynecomastia). This occurred in 0.4% of men on finasteride, but this was no greater than in the control group. Other side effects that were not statistically significant included hypersensitivity reactions including rash, pruritus, urticaria, swelling of the lips and face, and testicular pain. No interactions with finasteride and other drugs have been identified.
Finasteride causes a decrease in serum PSA (prostate specific antigen) by approximately 50% in normal men. Since PSA levels are used to screen for prostate enlargement and prostate cancer, it is important that ones personal physician is aware that he is taking the medication, so that the doctor may take this into account when interpreting PSA results.
A study in the The New England Journal of Medicine in 2003, on finasteride 5mg (not Propecia) reported that men treated with finasteride 5mg for seven years had a 25 percent reduction in prostate cancer compared to the men treated with placebo. The study also showed high grade prostate cancers in 6.4% of the men treated with finasteride 5mg, compared to 5.1% in the placebo group. The authors concluded that finasteride 5mg prevents, or delays, the appearance of prostate cancer and that this possible benefit and a reduced risk of urinary problems must be weighed against sexual side effects and the increased risk of high-grade prostate cancer.
The explanation that has been proposed for the identification of higher grade tumors is that since the finasteride shrunk the benign tissue, the malignant part of the tumor was more easily reached with the needle biopsy. Supporting this explanation is the fact that those on Proscar had no more problems with their prostate disease than the controls. It is not known if this explanation is the correct one and what the effects a smaller, 1mg dose might have. Additional studies need to be done to have a definitive
Finasteride has not been approved for women. In addition, women should not handle crushed or broken Propecia tablets when they are pregnant, or may potentially be pregnant, because of the possibility of absorption of finasteride and the subsequent potential risk to a male fetus. Propecia tablets are coated and will prevent contact with the active ingredient during normal handling, provided that the tablets have not been broken or crushed. In spite of these cautions, exposure of pregnant women to semen from men treated with Propecia poses no risk to the fetus.
Merck recently carried out a study to evaluate the efficacy of finasteride in post-menopausal women. After one year there was no significant hair growth and, as a result, the study was terminated. An explanation is that hair loss in women is related more to the action of the enzyme aromatase (which is unaffected by finasteride) rather than DHT. It is also possible that the low DHT levels observed in postmenopausal women are responsible for the lack of significant response to finasteride.
Men experiencing hair loss often think of either using medication or having a hair transplant; however, the two treatments are not mutually exclusive. Finasteride has shown to be useful in complementing a hair transplant for a number of reasons:
- Finasteride works best in the younger patient who may not yet be a candidate for hair transplantation. Surgery can be used when the patient is older if the balding has progressed.
- Propecia can re-grow, or stabilize hair loss in the crown, where a hair transplant may not have been performed.
- Propecia is less effective in the front part of the scalp, the area where surgical hair restoration can offer the greatest cosmetic improvement.
For those who choose not to take Propecia, or who cannot take it due to its side effects, surgical hair restoration is just as effective. The only difference is that medications can prevent further hair loss whereas surgery cannot. It is important to note that medications are not needed for a hair transplant to be successful or for the transplanted hair to grow and be permanent.
Regarding the “optimal dose”, patients sometimes ask if they “can get away with taking less?” Research shows that there is a dose-response relationship between 0.2 and 1 mg/day, with the lower dose showing reduced efficacy. Therefore, unless one is having side effects, it is best to take the recommended dose of 1mg a day. There is also little evidence that a higher dose helps, although doctors do increase the dose under certain circumstances. Even though the data shows that 5 mg is no better than 1 mg, the dosage is often increased when someone has been on the same dose of medication for three to five years and then stops responding (begins to lose hair after being stable).
Finasteride 5mg (brand name Proscar) is available in a generic formulation. For those who want to take generic finasteride, we recommend purchasing a pill cutter at the pharmacy and taking ¼ of a 5mg tablet every day. Be advised that there is no scientific data insuring that this will be as effective as Propecia 1mg a day. Also, remember that there is a potential risk to pregnant women from handling broken or crushed tablets.
It is recommended that men aged 50, or over, should inform their regular physicians or urologists if they are taking Propecia for hair loss. It is also recommended that all men aged 50 or over have a routine annual evaluation for prostate disease, regardless of whether or not Propecia is used. For those patients who are of African descent and/or who have a family history of prostate disease, these recommendations would apply beginning at age 40. An evaluation may include a rectal examination, a baseline PSA, and other tests that your examining physician feels are appropriate.
Propecia and Rogaine work synergistically since their mechanisms of action are different. Rogaine (minoxidil) stimulates the hair follicle directly, but Propecia (finasteride) permits hair growth by blocking the negative effects of DHT. Of the two, Propecia is far more effective. It is reasonable to use the two together as long as the medications are used regularly. For patients contemplating surgical hair restoration, we generally have them continue Propecia only, since applying minoxidil is too fussy and offers very little incremental benefit.
Finasteride: Fact vs. Fiction
There are many misconceptions about the use of finasteride for hair loss. The most common are:
Myth: Women can’t touch the medication.
Fact: Pregnant women should not handle crushed or broken tablets
Myth: It only works in the crown.
Fact: It potentially works any where on the scalp where there is some hair, even in the front of the scalp.
Myth: Once you start it you must take it for ever.
Fact: You can stop the medication any time you want – you just lose its benefits when One stops.
Myth: Finasteride lowers testosterone
Fact: The medication, on average, causes a rise in serum testosterone levels by 9%.
Myth: The sexual side effects are frequent and irreversible.
Fact: The sexual side effects occur in 2% and are completely reversible when the
medication is stopped.
Myth: Finasteride causes birth defects if a man takes it when his wife is pregnant.
Fact: Exposure of pregnant women to semen from men treated with Propecia poses no risk to the fetus.
Myth: Propecia was originally a prostate medication that was found to prevent hair loss.
Fact: Propecia is not a prostate medication that was by chance noted to have a side effect of hair growth, it is a medication that was known since its discovery that it could grow hair.
In 2002, the FDA approved Avodart (dutasteride 0.5mg) for the treatment of prostate enlargement in men (the medical term is benign prostatic hyperplasia or BPH). Dutasteride is not approved for the treatment of male pattern hair loss. In fact, the clinical trials for hair loss were discontinued, so there is no safety data for its use in younger patients.
Like finasteride (the active ingredient in Propecia), dutasteride is an inhibitor of the enzyme 5 alpha-reductase that is responsible for the conversion of testosterone to DHT (dihydrotestosterone). However, unlike finasteride, which only inhibits the Type I form of the enzyme, dutasteride inhibits both the Type I and Type II forms of the 5 alpha-reductase enzyme. This dual effect makes the drug more potent, but it also increases the incidence of adverse reactions.
The Type II form of the enzyme is found predominantly in the hair follicle. The Type I form of the enzyme has been found in the scalp and sebaceous glands, but its exact role in hair growth has not been determined.
Dutasteride 0.5mg/day decreases serum DHT 91% and scalp DHT 54%. (Finasteride 5mg/day decreases serum DHT 71% and scalp DHT 38%). Based on these effects, one would expect that dutasteride would be more effective in the treatment of androgenetic alopecia than finasteride. However, since the Type I form of the 5 alpha-reductase that dutasteride blocks is not present in significant quantities in the hair follicle, these effects may not be as significant as one might expect. Controlled clinical studies are needed to answer this important question.
There is a greater incidence of sexual side effects with dutasteride compared to finasteride. Dutasteride was investigated in controlled multi-center studies involving men aged 50 and above with prostate enlargement. Drug-related side effects during the first six months were as follows: impotence (4.7%), decreased libido (3%), breast tenderness and breast enlargement (0.5%) and ejaculation disorders (1.4%).
The incidence of most drug-related sexual adverse events decreased with duration of treatment. The incidence of drug-related breast tenderness and breast enlargement remained constant over the treatment period. Ejaculate volume may be decreased in some patients with continued treatment; however, this decrease did not appear to interfere with normal sexual function.
As with finasteride, dutasteride reduces the amount of PSA measured in the blood and this must be taken into account when PSA levels are used in the detection of prostate cancer. Women who are pregnant or may become pregnant should not handle dutasteride because of possibility of absorption of dutasteride and subsequent potential risk to a male fetus.
The half life of dutasteride is 5 weeks compared to 6-8 hours for finasteride and serum concentrations of dutasteride are detectable up to 4-6 months after discontinuation of treatment. Therefore, men treated with dutasteride should not donate blood until at least six months after their final dose to prevent giving dutasteride to a pregnant woman through a blood transfusion. Men with liver disease should talk to their doctor before taking dutasteride.
One last point regarding Dutasteride. Men in families that had a deficiency of the Type II 5-alpha reductase enzyme (the enzyme blocked by finasteride) were followed for years without showing any adverse effects. However, there is no natural biologic model for the blocking effects of dutasteride; therefore, we have less information about the long-term effects of dutasteride, than we do with finasteride.
Continue reading reading this hair transplant book:
Chapter 7 – Hair Transplant Basics »»
Table of Contents
|Chapter 1||Brief History of Hair|
|Chapter 2||Hair and Its Functions|
|Chapter 3||Causes of Hair Loss|
|Chapter 4||Hereditary Baldness|
|Chapter 5||Psychology of Hair Loss|
|Chapter 6||Hair Loss Medications|
|Chapter 7||Hair Transplant Basics|
|Chapter 8||Follicular Unit Transplantation|
|Chapter 9||Follicular Unit Extraction|
|Chapter 10||Master Plan for Restoring Hair|
|Chapter 11||Goals and Expectations|
|Chapter 12||Numbers of Grafts Needed|
|Chapter 13||Hair Transplant Repair|
|Chapter 14||Hair Loss in Women|
|Chapter 15||Hair Systems and Camouflage|
|Chapter 16||Preparing for a Hair Transplant|
|Chapter 17||The Hair Restoration Procedure|
|Chapter 18||What to Expect Following Surgery|
|Chapter 19||Hair Transplant Fallacies|
|Chapter 20||Choosing Your Doctor|
|A Final Note|
|About the Author|