Q: Can Propecia (finasteride) completely halt androgenic alopecia for the duration of your lifetime, or does it just slow down the progression of androgenic alopecia? — L.B., Scarsdale, N.Y.
A: In many patients we have found finasteride to hold on to a patient’s hair for at least 15 years. We don’t have much longer data than that since it was approved for hair loss in 1998. Although finasteride will usually continue to work as long as you take it, it may lose some of its efficacy over time. Generally after about 5 years we may notice that the patient’s hair is starting to thin again and we will increase the dose slightly. It is important to understand that even if someone thins on finasteride it doesn’t mean the medicine is not working, because they might have thinned much more without it. To my knowledge, there are no studies that have looked at the effects of finasteride for such an extended period of time.
Q: I have been taking finasteride for several years and I seem to be doing well. Does finasteride generally work long-term? — A.C., West University Place, Texas
A: With regard to efficacy, a recent long-term, uncontrolled study by Rossi et al. reported that the beneficial effects of finasteride on hair growth continued as time goes on and that a significant proportion of patients, unchanged after 1 year, improved later on. In addition these patients maintained a positive trend over time -– up to ten years. When comparing different age groups, they found that subjects older than 30 years showed a better hair growth in the long term than those who were younger. Of the 113 patients in the study followed for 10 years, only 14% worsened, whereas the remaining 86% had benefits.
The central finding of a 2004 study led by Italian researcher Dr. Antonella Tosti, in which he and his team investigated sexual dysfunction in hair loss patients being treated for androgenetic alopecia, was that there was no statistically significant change in sexual function after four to six months of treatment with finasteride 1mg (Propecia).
The researchers used a questionnaire, called the abridged 5-item version of the International Index of Erectile Function (IIEF-5), to measure sexual function in the men in the study. The questionnaire, which is considered an internationally valid diagnostic tool for distinguishing between men with and without erectile dysfunction, asks the patients 15 questions on the topics of: erectile function, orgasmic function, sexual desire, intercourse satisfaction, and overall sexual satisfaction. By administering the questionnaire both before and after treatment with finasteride, the researchers were able to determine if sexual function was impaired by the treatment.
The result of this investigation in the sexual function of 186 patients was that, “the erectile function of all patients remained stable after 4 to 6 months of treatment with finasteride 1 mg.”
Interestingly, the research team found that sexual side effects were actually less common than reported in the clinical trials of the drug. They suggest that this difference was potentially due to the fact that subjects in the clinical trials were made aware of the potential for sexual side effects, and were asked about these side effects upon each visit, which led to higher reporting of side effects than what would otherwise be the case.
Reference:
Tosti A, Pazzaglia M, Soli M, Rossi A, Rebora A, Atzori L, Barbareschi M, Benci M, Voudouris S, Vena GA. Evaluation of Sexual Function With an International Index of Erectile Function in Subjects Taking Finasteride for Androgenetic Alopecia. Arch Dermatol. 2004;140:857-858.
The 2011 study published by a research team led by Dr. Alfredo Rossi, is the first comprehensive investigation on long-term safety and efficacy of finasteride 1mg (Propecia).
In “Finasteride, 1 mg daily administration on male androgenetic alopecia in different age groups: 10-year follow-up,” the Italian research team sought to fill a gap in our understanding of the long-term effects of treating hair loss with Propecia. The study tracked hair growth in 118 men between the ages of 20 and 61, with mild to moderate hair loss, who were treated with 1mg finasteride. These patients were evaluated before treatment and then again at 1, 2, 5, and 10 years on treatment.
The result of testing found not only that Propecia works and is safe for use, but there were some other interesting findings as well. Only 14% patients experienced a worsening of hair loss, while 86% benefited from the treatment over this extended time period and efficacy of the drug was found not to reduce over time for the majority of patients.
One of the most interesting findings is that patients who had hair growth in their first year of treatment are more likely than others to have better hair growth after 5 years. About half of patients experienced good hair growth in their first year, and about 53% of those patients went on to see improved growth over time. However, of the group with unchanged or worse results in their first year, only 25% saw improved hair growth after 5 years. After 10 years, almost 69% of patients who experienced growth in their first year experienced continued growth. Only 32% of those who saw unchanged or worse results after their first year had growth at 10 years.
The authors concluded that a patient’s response to finasteride in the first year is a pretty good indicator of how effective long-term treatment will be for the patient. The better growth he experiences in his first year, the more likely he will have continued growth beyond 5 years of treatment.
Among other findings, the age of a patient did have a statistically significant effect on the outcome, as patients older than 30 years had better hair growth in the long term. On the topic of side effects, 7 subjects (5.9%) experienced them, and some of those patients remained in the study because of what they perceived as the benefits of the treatment.
In conclusion, the authors found that Propecia is a safe and effective hair loss medication, even when used long-term. It is effective in patients older than 40 years and it is particularly beneficial for patients over 30 and who are in early stages of hair loss. Perhaps the most important finding is that a patient’s response to finasteride after the first year of treatment can be an indicator of the patient’s success with the drug in the long-term.
Reference:
Rossi A, Cantisani C, Scarnò M, Trucchia A, Fortuna MC, Calvieri S. Finasteride, 1 mg daily administration on male androgenetic alopecia in different age groups: 10-year follow-up. Dermatol Ther 2011; Jul-Aug;24(4):455-61.
Led by Dr. A. Sato, a Japanese team of medical researchers published the largest finasteride study ever performed, “Evaluation of efficacy and safety of finasteride 1mg in 3,177 Japanese men with androgenetic alopecia.” It investigated the effects of finasteride over a 3 1/2 year period in men with androgenetic alopecia, or common baldness.
The study found that patients who had experienced hair loss for an extended period of time and were treated with finasteride exhibited notable hair growth. While a fairly small proportion of patients with a hair loss duration over 10 years exhibited “greatly increased” growth, 85% of patients with hair loss duration of more than 15 years experienced “moderate” or “slightly increased” growth. Physicians have thought that people with advanced hair loss do not respond as well as patients in the early stages of hair loss. However, in light of the results of this study, that determination should be reconsidered.
Further, the same study found that the initial age of a hair loss patient at the time of commencing treatment has little to no effect on the outcome. While the efficacy studies that are included in the Propecia package insert were conducted in men 18 to 41 years old, men over 41 appear to respond as well as the younger group. Adverse reactions occurred in only 0.7% of the study population and the Sato study found no increase in adverse safety events over time.
In summary, the Sato study showed an increased response rate to finasteride 1mg with increasing duration of treatment. In addition, it is effective in a larger portion of the male population with androgenetic alopecia than previously thought.
Reference:
Sato A, Takeda A. Evaluation of efficacy and safety of finasteride 1mg in 3,177 Japanese men with androgenetic alopecia. J Dermatol 2012; 39: 27–32.
Q: I heard that Propecia stops working after five years. Is this true and why in five years? — B.P., Stamford, CT
A: That is not correct. Although the effects of Propecia (finasteride 1mg) will diminish over time, it does continue to work. Using finasteride long-term will still be better than stopping it at some arbitrary interval. In clinical practice, I often increase the dose of finasteride, after someone had been on the medication 3 to 5 years, to help maintain its effectiveness.
Q: I have a friend who has been using Propecia 1mg a day for twelve months without having any regrowth. Is he likely to experience regrowth at this stage? — S.S., Long Island, NY
A: Your friend is unlikely to get any significant regrowth after one year, but that doesn’t mean that the medication is not working. He may have had even more hair loss without the medication.
Q: I have early thinning on the top of my scalp and I was told to use Propecia, but I heard that is was only for men. What do you think? — T.G., Staten Island, NY
A: Women can’t take Propecia during the child-bearing years because, if ingested, it can cause birth defects in male offspring.
In post-menopausal women, where we see the greatest frequency of hair loss, it doesn’t seem to be effective.
In pre-menopausal women who do not plan to become pregnant or who already have children, we are still cautious about using the medication, since there effectiveness has not been proven and its long-term safety in this population has not been tested.
