When it comes to hair loss treatments for men, many products make bold claims without being backed up by much in the way of medical science.
As a treatment for hair loss, finasteride (commonly sold as Propecia®) works by reducing your body’s production of the androgenic hormone that causes baldness.
Research shows that it’s very effective. In fact, several studies have found that most with visible hair loss who use finasteride experience either a reduction in hair shedding or improvements in hair growth.
If you’ve recently started using finasteride, you may have noticed a positive change in your hair, whether it’s extra growth around your hairline or new thickness on top.
Below, we’ve covered how finasteride works to treat hair loss, as well as the steps that you can take to maintain your results while using this medication.
We’ve also shared several techniques that you can use to improve your results from finasteride with other hair loss medications, hair care products and more.
Finasteride works by preventing your body from converting testosterone into a more potent male sex hormone called dihydrotestosterone, or DHT.
To understand how finasteride works as a treatment for hair loss, it’s important to quickly explain the basics of DHT and its role in male pattern baldness.
DHT is an androgen, or male sex hormone. Before you’re born, it plays a key role in developing your male genitals.
During adolescence, DHT is responsible for producing male secondary sex characteristics, such as your facial and body hair.
As an adult, DHT no longer plays a major role in your physiology. However, if you’re genetically predisposed to male pattern baldness, DHT can bind to receptors in your scalp and shrink your hair follicles through a process referred to as miniaturization.
Male pattern baldness varies in severity from one man to another. While some men only lose a small amount of hair, others have significant hair loss that worsens over time.
Enter finasteride. Finasteride belongs to a class of medications referred to as 5-alpha-reductase inhibitors, or DHT blockers.
It works by blocking the enzyme that converts a small amount of the testosterone produced by your body into DHT.
By preventing your body from converting testosterone into DHT, finasteride helps to shield your hair follicles from DHT-related damage and treat male pattern baldness.
Over the long term, finasteride works well as a treatment for hair loss. In fact, a 10-year study of finasteride found that more than 99 percent of men who use it experience no further progression of their hair loss over the long term.
However, results from finasteride aren’t immediate. It usually takes three to four months before any results are visible, with the “final” results from finasteride visible after about one year.
During the first few months of treatment with finasteride, some guys experience more hair loss than normal -- a phenomenon that’s known as finasteride shedding, or Propecia shedding.
This might seem odd for a hair loss medication. After all, if finasteride works by preventing your body from producing DHT, how can it make your hair loss worse?
Currently, although experts aren’t completely sure why finasteride often causes temporary hair shedding, some believe it may be related to your hair’s growth cycle.
Every hair on your body completes a multi-phase growth cycle that involves growth, regression, rest and shedding.
During one phase of this cycle, which is referred to as the anagen phase, your hair grows to its full length before resting and falling out.
The anagen phase for hair on your scalp typically lasts for several years. It’s much shorter for your body hair, which is why the hair on your arms, legs and torso naturally grows to a shorter length than the hair on your scalp and face.
When DHT binds to and damages your hair follicles, it can shorten the anagen phase so much that new hairs eventually stop growing out from your scalp.
After you start using finasteride, your DHT levels drop significantly. In fact, research shows that a typical dose of finasteride lowers the amount of DHT that can freely circulate throughout your body by more than 70 percent.
Finasteride actively promotes your hair follicles to enter into the anagen, or growth, phase of the hair growth cycle.
Due to this decline in DHT levels and sudden promotion of hair growth, hair follicles that were in the regression and resting phases of the hair cycle may become active again.
This may cause temporary hair loss as some of your hair follicles shed old hairs to replace them with new ones.
Finasteride shedding can be particularly severe if you also apply minoxidil, a topical medication designed to stimulate hair growth, to your scalp.
Minoxidil works by encouraging your hair follicles to enter into the anagen phase of their growth cycle.
Like finasteride, it’s known for causing temporary hair loss during the first few weeks or months of use.
If you start to experience hair shedding after you start using finasteride either on its own or with minoxidil, it’s important to stay the course.
Finasteride does work, and the hair shedding you may experience during the first few weeks or months of treatment is a temporary issue.
Keep using finasteride as prescribed and after three to four months, you should begin to see real improvements in your hair.
After you’ve been using finasteride for six months to one year, you may be able to see a positive change in your hair’s thickness, density and overall appearance.
Although finasteride works as a treatment for hair loss, it requires commitment and consistency to produce lasting results.
To maintain your results from finasteride, make sure to:
While finasteride is effective on its own, it’s even more effective when combined with other hair loss treatments and hair care habits.
Below, we’ve shared several techniques that you can use to improve your results from finasteride.
Minoxidil, a topical hair loss medication, is very effective at stimulating hair growth and treating hair loss when it’s used alongside finasteride.
In one study, researchers compared the effectiveness of finasteride and minoxidil alone with a combination of the two medications.
They found that 59 percent of men who only used minoxidil and 84.1 percent of men who only used finasteride experienced improvements in hair growth after 12 months.
In comparison, a significantly higher 94.1 percent of men who used both hair loss medications together experienced improvements in hair growth.
Our guide to applying minoxidil for hair growth explains how you can add minoxidil to your hair loss prevention routine.
Many hair loss prevention shampoos, including our Thickening Shampoo, contain ingredients that may help to reduce DHT levels in your scalp.
It’s worth noting that although these ingredients appear to be effective, the scientific evidence for them isn’t as strong as it is for finasteride or minoxidil.
You can find out more about these ingredients and their effects in our detailed guide to what to look for in a men’s hair loss shampoo.
Vitamin B7, or biotin, is a vitamin that plays an important role in the growth process for your hair, skin and nails.
Other vitamins also play key roles in the growth and maintenance of your hair, including vitamin A, B12, C, D and E.
While vitamins don’t appear to have any significant role in preventing male pattern baldness, it’s important to consume a healthy amount of vitamins to keep your hair in optimal condition.
Smoking isn’t just harmful for your heart and lungs -- it can also damage your hair follicles and contribute to hair loss.
The chemicals in cigarettes can do serious harm to your skin and hair, including by damaging the DNA inside your hair follicles.
A study carried out in Taiwan even found that regular cigarette smoking was associated with a higher risk of developing moderate or severe hair loss in men.
Other scientific research shows that smoking may reduce your skin’s elasticity, causing you to develop wrinkles and other signs of aging early.
If you’re a smoker, consider quitting. Our guide to quitting smoking shares techniques that you can use to control nicotine cravings, stay focused and make real progress towards kicking the habit for good.