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.
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.
Download the Rossi study of finasteride long-term effects