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What it is

Propecia (finasteride): Propecia is a prescription medication approved by the United States Food and Drug Administration (US FDA) originally as a prostate gland shrinking medication, however in 1998 it was also approved at a lower dosage as an anti-baldness treatment. It is sold as a prescription prostate medication in 5 milligram tablet form under the brand name Proscar. For treatment of hair loss it is sold in 1 milligram tablets under the brand name Propecia.



How it works

5 milligram finasteride tablets have been approved as a safe and effective for treatment for prostate enlargement because it has been shown that finasteride effectively blocks the enzyme that converts testosterone into a form that enlarges the prostate gland. It was discovered that the same form of testosterone that is responsible for some prostate gland enlargement, also plays an important role in signaling certain genetically predisposed hair follicle cells to miniaturize, eventually leading to hair loss. By blocking the conversion of testosterone from one form to another, Propecia helps stop hair loss, and in many cases regular Propecia use actually results in significant hair regrowth.

Lower Dosage to reduce Baldness

It is significant to note that the hair loss reduction effect of Propecia occurs even at a much lower dosage than that needed to treat enlarged prostrate glands. A single 1 milligram Propecia tablet (finasteride) taken daily is the usual prescribed dose for hair loss treatment. Over time, some patients find that in addition to halting hair loss, they actually start to regrow hair that had recently been lost. Dr. Panagotacos prescribes finasteride treatments for certain of his hair restoration patients. This patient illustrates an exceptionally positive response to finasteride treatment. Typical results are less pronounced.

Clinical evidence suggests Propecia works to slow the rate and degree of hair loss, and in some cases reverse hair loss, in the following manner:

Lower Dosage to reduce Baldness


5-alpha-reductase increases DHT: Without Propecia, testosterone, a naturally occurring hormone in the bloodstream, is converted by the naturally occurring enzyme 5-alpha-reductase to a form of testosterone called dihydrotestosterone (DHT).

5-alpha-reductase increases DHT


DHT affects hair follicles: In men with pattern hair loss, certain scalp hair follicles are genetically predisposed to respond 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 by elevated DHT levels. The response is a shortening of the growing phase of the hair follicles, and the progressive miniaturization of the hair follicles. The end result is shorter and smaller hairs, and eventually a decrease in the number of visible hairs on the scalp.

DHT affects hair follicles


Propecia blocks type II 5-alpha-reductase: Propecia blocks a form of 5-alpha-reductase called type II 5-alpha-reductase from converting as much testosterone to DHT as would be the case without treatment. The result is lower levels of DHT in the blood. Continuous treatment is required to maintain the benefits, as 5-alpha-reductase will continue converting testosterone to DHT if treatment is discontinued.

Propecia blocks type II 5-alpha-reductase


Propecia protects susceptible hair follicles: The lower levels of DHT in the bloodstream appear to inhibit susceptible hair follicles from further miniaturization. This effect slows, and in many cases stops further hair loss.

Propecia protects susceptible hair follicles


Some miniaturized follicles start to grow larger: Over time, in some individuals, some miniaturized hair follicles begin to grow back to normal size, and begin to grow normal size hairs again. The degree of hair regrowth can vary from no measurable regrowth to significant regrowth.

Some miniaturized follicles start to grow larger


Finasteride Benefits

Propecia stops pattern hair loss: Tests have shown that Propecia treatment prevents miniaturization of hair follicles, and thereby stops hair loss. Finasteride prevents the aging of hair follicles and 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 (Blue bars). 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 (Red bars). After the first two years, results of the group taking Propecia continued to improve.

Propecia can help regrow lost hair: In another 2-year clinical trial, 66% of men taking Propecia had visible hair regrowth at the vertex (top of the head), while only 7% of men taking a placebo had regrowth (Yellow). Only 1% of men taking Propecia had hair loss at the top of their heads, while 33% of men taking a placebo showed a decreased hair count in this area (Red). A five year study has shown essentially the same results.

Propecia can help regrow lost hair


Safety: A level of safety has been established for finasteride for many years before it was approved as a hair loss treatment. 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 hormones. Propecia is not an antiandrogen.

Finasteride is approved as safe and effective in tablet form for treating some forms of enlarged prostate gland. It has been shown to be effective at stopping hair loss when taken by mouth in table form at much smaller doses than that used to treat enlarged prostate.

Beneficial side-effects: Some possible side effects of finasteride treatment for hair loss may be seen as beneficial, such as the shrinking of the prostate gland in men susceptible to an enlarged prostate.

Beneficial side-effects


Propecia Risks

Men only: Propecia is for men only, and is not approved by the FDA as a hair loss treatment for women or children.

Pregnancy: Women who have become pregnant while taking finasteride should immediately discontinue the finasteride treatment. If treatment is continued, finasteride may cause a male fetus to develop ambiguous genitals, and have female characteristics.

Less sex drive: Finasteride 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.

Reduced ejaculate: There is a risk of reducing the volume of ejaculate by up to 20% if the prostate gland is reduced in size, as a result of finasteride treatment. Sperm activity remains normal.

Finasteride Variations

Finasteride by mouth: A single one milligram Propecia tablet is typically taken by mouth on a daily basis.

Finasteride topical lotion: Finasteride lotion is not commercially available, however Dr. Panagotacos does offer this treatment mixed with other medications to block DHT to certain of his patients, and an examination is required for a prescription. Applying the lotion is not as effective as swallowing the tablets. Grinding up finasteride tablets to make a lotion will not work, as finasteride does not dissolve easily. Topically applied finasteride is reserved for use by those who wish to block only 5-10% of the DHT activity in the scalp, which is a lower level than typically achieved from ingesting tablets. Finasteride lotion must be specially prepared by a Pharmacologist or Medical Doctor specializing in medical hair restoration.

With Minoxidil: Studies have shown that combining oral finasteride (tablets) and topical minoxidil (lotion) produces better results than just taking the tablets or using the topical medication alone.

Finasteride, Proscar, Propecia History

Dominican Republic:

The story of finasteride begins with scientists who were working with certain Dominican Republic people 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, most of these young boys normalized. They eventually had children of their own, and perpetuated the genetic trait.

No hair loss: It was also observed that the adult males in this group being studied never suffered enlarged prostate glands, never developed prostate cancer, nor did they lose their hair. No male pattern hair loss! Genetic research showed that their gene for producing the 5-alpha-reductase enzyme was inactive. With no 5-alpha-reductase enzyme, testosterone was not readily converted to DHT.

5-alpha-reductase regulation: Scientists figured that if they could create or find 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 hair loss prevention.


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