FAQ's - Finasteride

Q. How long has finasteride been available as a treatment for MPB? 
A. The 5mg tablets of finasteride (Proscar®) were introduced by the Merck Co. in 1992 as a medication to treat the symptoms of benign prostatic hypertrophy.  Some men taking Proscar® reported improved hair growth.  Subsequently, the Merck Co. announced the availability of Propecia®, a 1mg finasteride tablet, approved by the U.S. FDA in December 1997.  Finasteride works by inhibiting the Type II 5alpha-reductase with resulting decreased serum levels of dihydrotestosterone (DHT).

Q. What are the side effects of taking finasteride? 
A. A percentage of male patients taking finasteride report decreased libido. Although Merck claims that the number of patients who experience decreased libido is less than 3-4%, we have found that the incidence of side effects is considerably higher. About 1 or 2 percent of men report relative impotence. There have also been reports of an "ache in the groin area" by a small number of male patients. The symptoms disappear when the medication is discontinued. Even if the patient continues to take the finasteride, the symptoms usually resolve themselves for most patients.

Q. What other side effect might it have? 
A. Somewhere between 20 to 25% of men report a decreased volume of ejaculate. There is no change in the sperm count or motility or morphologic features.

Q. How can I be sure of oral finasteride's long-term safety? 
A. You cannot be certain, because finasteride has only been in widespread use for less than two decades. But, fortunately, there is a naturally occurring control group. There are people who have a congenital 5 alpha-reductase deficiency and they're perfectly normal adults, except they always have a great head of hair; their prostate does not enlarge; and their incidence of prostate cancer is close to non existent.

Q. Does this mean that taking finasteride will help prevent prostate cancer? 
A. No, that would be presumptuous. However, Merck conducted a prospective seven-year study of men taking 5 mg finasteride/day to determine whether or not they have a smaller incidence of prostate cancer as compared to a matching population and, in fact, they did.

Q. Will taking finasteride cause birth defects? 
A. The probability is essentially nil and there has not been a single case report of a birth defect due to a male patient taking finasteride. The association of a lack of DHT and birth defects is that a woman who has a congenital severe deficiency of 5 a-reductase can give birth to a male child with abnormalities of his urinary tract and be born as a pseudo hermaphrodite.

Q. Do you ever recommend finasteride for women? 
A. There is no contraindication for post-menopausal women or for women who are sterile for any other reason. However, recent clinical trials conducted by Merck show no statistical benefit for post-menopausal women who have pattern baldness to take finasteride.

Q. Will I have to take finasteride for the rest of my life? 
A. Like minoxidil, finasteride is not a cure for baldness. You should continue to take finasteride to keep the levels of DHT low and to maintain your hair growth. If you stop taking finasteride, it takes two weeks for the DHT levels to return to your baseline levels.

Q. Will taking finasteride have any effect on the hair on other parts of my body? 
A. Theoretically, it can. Hair on the top of the scalp is genetically encoded so that it is negatively affected by dihydrotestosterone (DHT). Ironically, mustache and beard growth are promoted by DHT. Elsewhere on the body (chest, underarms, pubis, etc.), the hair is affected by testosterone. Taking finasteride can elevate the levels of testosterone in the body by 10 to 20%. There have been rare reports of increased body hair (reflex hyperandrogenicity).

Q. Does finasteride help to grow hair in the frontal area of the scalp? 
A. It can, although it is not as effective as Xandrox® in doing so. Frontal regrowth is greatly enhanced when oral finasteride is taken concomitant with topical minoxidil.

Q. Does finasteride accumulate in the body? 
A. No. Finasteride has a biological half-life of 6 hours. So, in six hours, half of the finasteride that you took has already been eliminated from your body.

Q. How long does it take to see any results from taking finasteride? 
A. As a rule, three to six months.

Q. What is the recommended dosage of finasteride to promote hair growth? 
A. Clinical trials demonstrated that effective doses varied widely.  It was found that in some patients from 0.2 mg to 5 mg daily had similar results on the scalp.  With 1 mg doses, it was found that everyone within three standard deviations (99.7% of patients) responds to treatment.

Q. Do I have to take finasteride with food? 
A. No. Finasteride is easily absorbed in the small intestine with or without food. It’s best to take it at about the same time each day, so taking it becomes routine.

Q. Will finasteride change the level of testosterone in the body? 
A. There is an increase in the amount of testosterone in the serum, because a fraction of the testosterone is not being converted to dihydrotestosterone. On the average, the increase in the serum testosterone level is 10 to 20% and usually remains within normal limits. The feedback mechanism in the pituitary eventually stabilizes the testosterone level back to baseline levels. Rare cases of ‘reflex hyperandrogenicity’ have been reported with increased body hair and oily skin.

Q. Why does finasteride work better in conjunction with minoxidil solutions? 
A. These medications work in two entirely different ways, so their effects are more than synergistic; they’re additive. It is not known exactly why or how minoxidil promotes hair growth, but experience shows that using both medications is much more effective than using either one alone. As an example, although castration will stop the balding process, very few castrated men grow back much hair unless minoxidil is also applied to the scalp. The combined therapies have been found to be successful in the stump-tailed macaque, the only other animal that exhibits MPB). However, competing pharmaceutical companies are unlikely to fund a human trial for competing products.

Q. How do I get Propecia® (1 mg finasteride)? 
A. You can make an appointment at the Regrowth office for a doctor's consultation or see your family doctor for a prescription.

Q. Are there manufacturers of finasteride other than Merck Pharmaceutical? 
A. Yes.  The patent for Proscar® expired on 19 June 2006.  Teva Pharmaceuticals has been approved by the US FDA to market a 5mg finasteride tablet. Generic 1 mg tablets may also become available.  If you shop around you should be able to find the best price.  The finasteride is homogeneously distributed throughout the 5mg tablet of Proscar® and generic finasteride tablets. Use a pill cutter or any sharp blade and cut the hard tablets into four pieces. You will undoubtedly also create some powder and many smaller fragments. It really makes no difference if the pieces are of unequal size. The range of effectiveness is very wide and has been shown to vary as much as from 0.2 mg to 5 mg of finasteride. Furthermore, there is such a tight bond created between the finasteride and the Type 2 5AR, that even if you discontinue taking finasteride altogether, it will require two weeks for your DHT level to return to your baseline levels. So, a variation in the daily dosage is really inconsequential. There is probably no increase in the likelihood of having side effects by taking 1.25mg of finasteride as opposed to taking 1.0mg of finasteride. So, take just one quarter of a tablet once / day. The time of day doesn't really matter. Nor does it matter if you take it with or without food.

When you are getting a physical examination or are having laboratory tests on your blood, inform your doctor that you are taking finasteride.  Finasteride will decrease the PSA (Prostate Specific Antigen) level by approximately 50%. Assessing the PSA level is a screening test for possible prostate cancer.