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One medication, Propecia (finasteride), is typically prescribed for men only, due to possible side effects when taken by pregnant women. Another, Rogaine (minoxidil), is useful for treating both men and women. The last two, high-estrogen oral contraceptives and Aldactone (spironolactone) are generally prescribed for women only, due to the risk of undesirable feminizing side effects in men.
Propecia (finasteride):
The single most effective medication proven to treat genetic pattern hair loss is Propecia. It is prescribed for men with a genetic predisposition to hair loss (male pattern baldness). Propecia is the hair loss treatment medication brand name for the drug finasteride. Finasteride is a prescription medication that was first approved by the FDA for treating enlarged prostate glands. To the delight of some patients taking finasteride for enlarged prostate glands, a side effect of this medication was decreased hair loss, and often regrowth of recently lost hair.
After years of additional testing as a hair loss treatment, in 1998 finasteride was also approved in pill form, at a lower dosage, as an anti-baldness treatment. It is sold as a prescription prostate medication in five-milligram tablet form under the brand name Proscar. For treatment of hair loss, it is sold in one-milligram tablets under the brand name Propecia. For treating baldness, the lower dosage is adequate. The hair loss reduction effect of Propecia occurs at a much lower dosage than that needed to treat enlarged prostrate glands.
Finasteride effectively blocks one form of the 5-alpha-reductase enzyme that converts testosterone into DHT. By blocking the conversion of testosterone into DHT, Propecia prevents the "hair loss message" from getting to hair follicles that are genetically programmed to be sensitive to DHT. This helps stop further hair loss, and in many cases regular Propecia use actually results in significant hair regrowth of recently lost hairs.
Without Propecia, testosterone in the blood is converted freely by the enzyme 5-alpha-reductase into a form of testosterone called dihydrotestosterone (DHT). In men susceptible to pattern hair loss, certain scalp hair follicles are genetically predisposed to respond in a negative ways to elevated levels of DHT in the bloodstream. The most susceptible hair follicles are typically located at the temples, front, and top of the head, but all hair follicles may eventually be influenced to some degree by normal DHT levels. One negative response to DHT is a shortening of the growing phase of the hair follicles, and another is the progressive miniaturization of the hair follicles, which causes miniaturization of the hairs they produce. The end result is shorter and smaller hairs, and fewer and fewer hair follicles producing hairs.
Propecia blocks a form of 5-alpha-reductase found primarily in the prostate gland, called type-II 5-alpha-reductase, from converting testosterone to DHT. The result is lower levels of DHT in the blood. Over many years, DHT in the bloodstream signals hair follicles shorten their growing phase and to miniaturize. By reducing the amount of DHT in the blood, Propecia reduces the strength of the DHT hormone message, so many of the follicles that would have quit instead continue to produce new hairs.
| Without Propecia, testosterone in the blood is converted freely by the enzyme 5-alpha-reductase into a form of testosterone called dihydrotestosterone (DHT). |
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| Propecia blocks a form of 5-alpha-reductase found primarily in the prostate gland, called type-II 5-alpha-reductase, from converting testosterone to DHT. |
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Continuous treatment is required to maintain this benefit, as 5-alpha-reductase will continue converting testosterone to DHT if treatment is discontinued. However the benefit of using Propecia for any period of time is still realized; Propecia buys time for men with a genetic predisposition for hair loss. The DHT message to stop growing hair must continue for many years, and often many decades, for DHT-sensitive hair follicles to get the message and stop growing new hairs. If the DHT message is disrupted for a period of time, the clock is stopped. Another way of putting it is that a 30-year old man who would lose his hair by age 60 who uses Propecia for 20 years and then stops, will delay the age when he would lose his hair to age 80. The benefit of using Propecia for 20 years is not lost when use is discontinued.
With Propecia use, the rate of hair loss slows, and in many cases stops. In many individuals, some recently miniaturized hair follicles begin to grow back to normal size, and begin to grow normal size hairs again. This results in increased hair. The degree of hair regrowth can vary from no measurable regrowth, to significant regrowth.
Double blind clinical tests have shown that Propecia helps men keep the hair they have. In one two-year study, 83% of men taking Propecia maintained their hair at the top of their heads (vertex area), compared to 28% of men taking a placebo. In the same study, 17% of the men taking Propecia still experienced measurable hair loss, but 72% of the men taking the placebo also experienced additional hair loss. After the first two years, results of the group taking Propecia continued to improve.
In addition to stopping further hair loss, Propecia can also help regrow recently lost hair: In another 2-year clinical trial, 66% of men taking Propecia had measurable hair regrowth at the vertex, while only 7% of men taking a placebo had regrowth. In this study, only 1% of men taking Propecia continued to have hair loss at the top of their heads, while 33% of men taking a placebo showed a decreased hair count in this area.
For many years before it was approved as a hair loss treatment, a level of safety has been established for finasteride, the active ingredient in Propecia. As a prescription drug already approved by the FDA for treating enlarged prostate glands, it has been extensively researched and tested. Based on studies of hormone breakdown products found in the urine, it seems to affect only the 5-alpha-reductase enzyme, and not other hormones in the blood such as testosterone. Propecia is not an antiandrogen. In fact, levels of testosterone in the blood often increase by 10-15% when taking Propecia.
Finasteride has been shown to be effective at stopping hair loss when taken by mouth in tablet form at much smaller doses than that used to treat enlarged prostate glands. Some possible side effects of finasteride treatment for hair loss may be seen as beneficial, such as possible shrinking of the prostate gland in men susceptible to an enlarged prostate. My personal theory is that taking the lower dosage of finasteride in Propecia early in life may protect men with a genetic predisposition from suffering enlarged prostate glands and prostate cancer, as they get older.
A single 1-milligram Propecia tablet taken daily is the usual prescribed dose for hair loss treatment. Propecia is a treatment, not a cure. This means that a pill must be taken every day for the benefits to continue. When Propecia is discontinued, the hair loss process resumes.
Propecia is for men only, and is not approved by the FDA as a hair loss treatment for women or children. A woman taking finasteride would have only a small decrease DHT levels because most of the effect of finasteride is on type-II 5-alpha-reductase that is primarily made in prostate glands. Women who take finasteride and become pregnant may cause a male fetus to develop ambiguous genitals, and have female characteristics until puberty (at puberty, the child's genitals normalize).
Propecia treatment may cause a loss of sex drive in 1-2% of patients as a result of reducing levels of DHT circulating in the blood. Treatment with Viagra can be helpful in these cases, or discontinuing Propecia eliminates this possible side effect.
As a result of Propecia treatment, there is also a small risk of reducing the volume of ejaculate if the prostate gland is reduced in size. Sperm activity remains normal. Discontinuing Propecia eliminates this possible side effect.
Both of these conditions can affect as many as 2% of men in the first month of use, but drop to about 1/2% when measured again after 2 years. The story of finasteride begins with scientists who were working with a family in the Dominican Republic who had a genetic trait that caused them to give birth to male children with ambiguous genitalia. Female babies were not affected. In many cases it was difficult to determine such an infant's gender by observation alone. At puberty, when hormone levels in these affected individuals increased, these young boys normalized. They eventually had children of their own, and perpetuated the genetic trait. It was also observed that the adult males in this group being studied did not suffer from enlarged prostate glands, never developed prostate cancer, nor did they lose their hair. No male pattern baldness! Genetic research showed that their gene for producing the 5-alpha-reductase enzyme was inactive. With no 5-alpha-reductase enzyme, testosterone in the blood was not readily converted to DHT. The low levels of DHT that resulted prevented their hair follicles from getting the message to have shorter growth cycles and miniaturization.
Scientists figured that if they could create a medication to regulate the activity of 5-alpha-reductase they could accomplish some of the positive effects of this genetic trait, such as prostate gland normalization and, later hair loss prevention.
Rogaine (minoxidil):
After years of testing and clinical trials, in 1988 Rogaine topical lotion became the first medication approved by the FDA for treating genetic hair loss. The medication is a colorless and odorless liquid applied to the scalp. Rogaine is the brand name for the drug minoxidil when used as a hair loss treatment in lotion form. Before 1988, minoxidil had already been FDA approved in pill form as a prescription medication for treating high blood pressure. The brand name for high blood pressure minoxidil pills is Loniten.
Research on minoxidil's potential as an anti-baldness medication started after some Loniten patients noticed substantial new hair growth, a condition doctors call hypertrichosis. Usually the new hair growth was on the head and was desirable, but in some cases it also occurred on the arms, back, chest, and other areas. So researchers worked on a lotion form of the medication that could be applied to the scalp or face to direct new hair growth only where it was wanted.
Starting in 1988, Rogaine lotion was available only by prescription, and only in a 2% concentration. In 1995, the FDA decided minoxidil lotion was adequately safe for use without a prescription and Rogaine was soon available over-the-counter, in pharmacies and grocery stores. Generic versions of Rogaine became available when the patent on minoxidil expired, and the range of concentrations increased up to 5%. Most people using minoxidil lotion choose the 5% strength lotion, because it produces slightly faster results than the 2% concentration.
Researchers are not certain exactly how minoxidil works to stop hair loss or increase hair growth. It is known that it does not affect DHT levels in the blood. Minoxidil is a vasodilator, meaning it helps blood vessels enlarge. Other vasodilators do not stop hair loss or increase hair growth.
And Rogaine only seems to work on active hair follicles still capable of producing some hair, even if the hair produced is just "peach fuzz." One symptom of people with genetic pattern hair loss is the progressive miniaturization of hair follicles at the end of each growth cycle, resulting in finer and finer hairs being produced.
Rogaine 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 Rogaine 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.
Clinical studies were run during which some men and women with pattern hair loss applied Rogaine to their scalps, and others with pattern hair loss applied a placebo: the same mixture of water, alcohol, and propylene glycol used in Rogaine, but without the minoxidil. The men and women selected for the study had thin hair or baldness on the top of their heads, where minoxidil is most effective at promoting hair regrowth. The effectiveness of the minoxidil treatment was compared to the placebo lotion. The results of clinical studies involving thousands of men and women have shown Rogaine is able to produce statistically significant increases in hair regrowth.
Those likely to achieve the best results with Rogaine are in the early stages of pattern hair loss. On average, younger people get better results than older people. Those with thinning or baldness on the top of their heads generally get better results than those with hair loss at the hairline. People with diffuse hair loss, especially women, tend to get better results than those with clear bald spots. Those with smaller bald spots usually show more regrowth than those with large bald spots.
Rogaine is applied on the scalp twice daily. It causes the hair-growing effect to take place on the scalp only, and not on other parts of the body. There is no effect on blood pressure when applied as directed. Rogaine is a treatment, not a cure. This means that the lotion must be applied to the scalp twice a day for the benefits to continue. Skipping a day or two occasionally is not likely to cause any measurable difference in the effectiveness of Rogaine treatment. However, after several months of discontinued use, the regrown hairs are likely to be shed.
Also, the hairs that would have been shed if the Rogaine had not prevented follicle miniaturization will also be lost as those follicles begin to shrink. So both regrown hairs and hairs that would have otherwise been lost if not for the Rogaine use may be shed within just a few months after discontinuing use of Rogaine.
Rogaine is safe. When used as directed and applied to the scalp, only very small amounts of it reach the blood. The risk of serious side effects is very small.
Hair transplant patients can use Rogaine. Many surgeons recommend using it within a few weeks after surgery to promote the growth of the transplanted hair follicles. Rogaine may also help reduce the tendency for mini and micro grafts to temporarily enter the telogen, or rest phase, immediately after being transplanted.
The most common side effect when used as directed is minor scalp irritation. In clinical studies involving 6,000 men and women about 7% of those using 2% strength Rogaine lotion experienced some degree of scalp itching, inflammation, dryness, or flaking. A smaller percentage of patients experience an increased pulse rate.
Some women using extra strength minoxidil lotion (5%) experience increased facial hair growth. This side effect tends to diminish after the first few months of treatment, or 2% minoxidil can be used. When treatment is discontinued normal facial hair growth resumes.
Rogaine treatment does not work on everybody with thinning hair. It is less effective for hair loss at the hairline than on the top of the head. It is less effective on large bald spots than small ones. It is less effective on small bald spots than on diffuse thin areas. It is less effective on long-established shiny bald areas than those with recent hair loss.
Rogaine takes time to produce results. When 2% Rogaine is used twice daily, it takes months to produce only a gradual change in appearance. Faster results may be achieved with 5% Rogaine. Several months are usually required before significant benefit can be seen. The results may improve further over the next several months with continuous twice-daily use. The maximum benefit is usually achieved after about 12 months of Rogaine use, and at that point hair regrowth tends to stabilize.
Some dermatologists prepare custom-blended minoxidil lotion, with added ingredients to reduce the risk of inflammation and increase absorption. One such additive is Retin-A (tretinoin): Tretinoin is a prescription acne medication applied to the skin, and is also well known for helping to reduce facial wrinkles. Rogaine applied with low concentrations of tretinoin has been show to promote greater hair growth, and possibly faster results, than Rogaine used alone. Tretinoin may increase the absorption of Rogaine through the skin, as well as having additional hair growth promoting effects. However, in addition to the risks and advantages of Rogaine use, tretinoin adds additional risk of skin irritation and inflammation.
Another Rogaine lotion additive is betamethasone valerate. Betamethasone valerate is a cortisone medication that helps to prevent scalp inflammation. In addition to reducing possible scalp irritation, it may also enhance the hair restoration effect of Rogaine in two ways: First, it helps block the metabolism of testosterone in the cells of the hair follicle where the hormone signal to "stop producing new hairs" takes place. Blocking this signal may keep more hairs growing. Second, betamethasone valerate helps to disperse the white blood cells that are called up to push the hair shaft out. In doing so, the white blood cells scar the hair follicle, reducing to a degree the follicle's ability to produce new hairs. By reducing scarring, betamethasone valerate may help keep the hair follicles active for more hair growth cycles. Male pattern baldness is a scarring alopecia, and the betamethasone valerate helps reduce scarring of the hair follicle.
Rogaine can be used at the same time as Propecia. The results are better than when either medication used alone.
High Estrogen Oral Contraceptives:
Women inherit a tendency for pattern hair loss just as men do. But in women the DHT message is usually blocked by relatively high levels of estrogens circulating in the blood. Estrogen levels begin to decline as women begin perimenopause around age 40, and by age 55 to 58 most women are in menopause. While testosterone levels usually decline along with progesterone and estrogen, the DHT message may finally start to get through, and thinning hair can result.
Birth control pills contain a combination of synthetic estrogen and progesterone hormones. Since they were first introduced in 1960, the estrogen component of oral contraceptives has been reduced from .150 milligrams per pill to .020-.035 milligrams. Today, a birth control pill with .035 milligrams of estrogen is considered a "high-estrogen" oral contraceptive. And for reference, the estrogen level in oral contraceptives is several times higher than that of most estrogen replacement medications prescribed for certain women after menopause.
Higher estrogen oral contraceptives such as Ortho Tri-cyclen or Ortho Novum often work well to inhibit production of androgens (including testosterone) by the ovaries and adrenal glands, which results in lower levels of DHT, and stops hair thinning.
Management of women's hormone levels is neither an easy task, nor one where medications are prescribed without careful consideration of the range of benefits and risks.
In addition to reducing androgenetic hair loss, the benefits of taking birth control pills include reduction of the risk of pregnancy, improved skin tone, reduced acne, and for women beginning the first stages of menopause, increased bone mass, decreased occurrence of hot flashes, somewhat tempered mood swings, and reduced irritability.
The risks of taking oral contraceptives include elevated risk of endometrial (uterine) cancer, and for older women an increased risk of cardiovascular complications such as heart attacks and strokes. There may also be a slightly elevated risk of breast cancer.
Aldactone (spironolactone):
Aldactone is the brand name for spironolactone, a prescription medication used in pill form for treating women with three common problems seen by dermatologists: acne, hirsutism (too much hair, especially on the face), and androgenetic alopecia. Spironolactone is a potent anti-androgen, and binds to DHT receptor sites on hair follicles, thereby blocking DHT from getting its hair loss message to the follicles. This medication is used only for women with androgenetic alopecia (genetic pattern hair loss), because it can produce undesirable side effects in men.
When used as a hair loss treatment, spironolactone is taken as a pill or made into a lotion that is applied directly to the scalp, usually along with Rogaine.
One disadvantage to spironolactone lotion is a disagreeable smell, which is made worse when combined in the same container with Rogaine.
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