If you’re a man looking to find practical treatment options for hair loss, you’ve no doubt heard of finasteride. In fact, that’s probably why you’re here.
Finasteride is the active ingredient Propecia® and is one of the most popular and effective hair loss medications available today. It’s also one of only two treatments for male pattern baldness approved by the FDA.
That’s because it works. Used on its own, finasteride has been shown to stop hair loss and even improve hair growth in the majority of men who use it, often within three to four months.
Finasteride comes in both oral and topical forms and is designed for use one time per day. It’s easy to use and, under the supervision of a healthcare professional, can stop male pattern baldness in its tracks without the need for costly cosmetic procedures or hair pieces.
However, like other medications, finasteride comes with its own risks.
There are also a lot of misleading finasteride warnings, which is why it's important to get the facts right before you start using it yourself.
In general, the risk of side effects from finasteride is low. Research shows the vast majority of men who use finasteride over the long term benefit from a successful hair loss treatment with few or no undesired results.
Low sex drive, erectile dysfunction, and ejaculation issues are a few of the known finasteride sexual side effects.
Some common ways to reduce finasteride side effects in men include following the prescribed dosage, taking the medicine at the same time every day, or taking a lower dosage, all of which should be done with the guidance of a healthcare professional who can help you safely take a lower dose.
If you’ve tried to avoid the side effects of finasteride and they persist, talk to your healthcare provider to learn about your other options.
Both topical and oral finasteride are prescription drugs used to treat hair loss caused by male pattern baldness or androgenetic alopecia. Finasteride belongs to a class of medications referred to as 5-alpha-reductase inhibitors, or 5ARIs.
Oral finasteride is a popular treatment for hair loss and has been approved by the U.S. Food and Drug Administration (FDA) for treating male pattern baldness since 1997. Unlike oral finasteride, topical finasteride hasn’t yet obtained approval from the FDA, but is sometimes prescribed off-label.
Propecia is the form of finasteride that’s used to treat hair loss. It’s available as a daily finasteride tablet at a 1mg dosage. Finasteride 1mg is what you’ll likely get if you have male pattern baldness or androgenetic alopecia.
The second is Proscar®, a high-strength finasteride dosage that’s prescribed to treat benign prostatic hyperplasia (an enlarged prostate). This medication contains 5mg of finasteride per tablet. While both medications cause similar side effects, the higher dosage has additional warnings, which we’ll cover in a bit, along with how to reduce the potential for finasteride side effects.
Finasteride works by inhibiting an enzyme called 5-alpha-reductase, which converts part of your body’s testosterone into dihydrotestosterone, or DHT — the primary culprit behind male pattern baldness.
This form of hair loss develops gradually due to the effects of DHT on the hair follicle (you can check out our complete guide on DHT and hair loss to learn more about this process).
This reduction in DHT levels protects your hair follicles from miniaturization, preventing male pattern baldness from becoming worse while stimulating re-growth in some patients.
And unlike many hair growth scams on the market today, these claims are backed by science.
For example, a 1998 study published in the Journal of the American Academy of Dermatology gave 1,553 men with male pattern hair loss daily oral finasteride over a two-year period and saw significant improvements in hair count.
A newer study from 2015 published in the journal Dermatologic Therapy found that 80 percent of the 450 men with pattern hair loss who used finasteride displayed improvements over the course of 12 months.
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Side effects are an unfortunate reality of almost all medications. However, using finasteride the right way may reduce your risk of developing side effects.
Try the following tips and techniques to use finasteride safely.
Finasteride is prescribed at a dosage of 1mg per day to treat male pattern baldness. There’s no need to take a higher dose than this, as it won’t improve your results. Using finasteride at a higher dosage may actually increase your risk of side effects.
Finasteride typically works best when it’s taken at approximately the same time every day. You can use finasteride with or without food. Learn more about the best time to take finasteride in our guide (spoiler alert: it doesn’t really matter when, as long as you’re consistent).
If you forget to take finasteride, skip the missed dose and continue your regular dosing schedule the next day. Do not take more than one dose of finasteride at a time.
Store finasteride at room temperature inside its original container. Information from the FDA notes that finasteride should be stored below 30°C (86°F), protected from light, and tightly closed. Avoid storing finasteride in the bathroom or other spaces with heat or excessive moisture
In certain cases, side effects are a temporary annoyance. Make sure to inform your healthcare provider so that they can track your progress and, if necessary, alter your dosage
Finasteride generally doesn’t cause interactions with other drugs. However, it’s still important to tell your healthcare provider about any other medications you use or medical conditions you may have.
Now that you know how to reduce the side effects of finasteride, we’ll touch on what the potential side effects are in the first place.
Like other FDA-approved medications, finasteride underwent a thorough testing process before it became available to the public.
Because of this, lots of data is available about its potential side effects, as well as its risks and drug interactions.
When looking into the side effects and common finasteride warnings, it’s important to be aware that two versions of finasteride are available.
Common Propecia side effects (1mg finasteride) include:
Erectile dysfunction (ED). In clinical trials, approximately 1.3 percent of men who took finasteride experienced erectile dysfunction, compared to 0.7 percent of men who used a non-therapeutic placebo.
Decreased libido. Approximately 1.8 percent of men who used finasteride 1mg reported a reduced interest in sex, compared to 1.3 percent of men who were treated with a non-therapeutic placebo.
Ejaculation disorder. In total, 1.2 percent of men who used finasteride reported issues related to ejaculation, with 0.8 percent reporting a lower semen volume. In comparison, 0.4 percent of men who used a placebo treatment reported lower semen volume.
Very few men who took finasteride in clinical trials experienced serious side effects.
In fact, only 1.2 percent of men who participated in finasteride clinical trials stopped using their medication because of adverse effects and only 3.8 percent of men who use finasteride for BPH reported experiencing any sexual side effects.
As you’d expect, side effects are more common with the higher-dose 5mg finasteride that’s used to treat BPH or benign prostatic hyperplasia.
In addition to the above side effects, Proscar lists two additional side effects, including:
Breast enlargement and/or tenderness (sometimes called gynecomastia)
Skin rash
Some of these side effects, such as sexual health issues, appear to become less common when finasteride is used over several years.
Another way to potentially reduce your risk of side effects is to switch to topical finasteride — a form of finasteride that you can apply directly to your scalp.
Like oral finasteride, topical finasteride works by reducing levels of DHT. However, it does so at a scalp level, meaning there’s less of a systemic effect of DHT levels in your bloodstream and throughout your body.
In one study, researchers found that topical finasteride is effective at treating hair loss, all with a reduced likelihood of adverse reactions.
We offer topical finasteride in our topical finasteride & minoxidil spray, which can be applied directly to your scalp to promote hair growth and prevent hair loss from worsening.
Wondering how to take finasteride without side effects? There’s no 100 percent guarantee that you can totally avoid side effects of finasteride (or any medication). However, if you’re looking into treating hair loss with oral or topical finasteride but are considered about side effects, here are some key things to remember:
While the side effects of finasteride may seem alarming at first, it’s important to keep them in context. The reason we know about these mild, uncommon side effects is that finasteride has been studied for decades and put through the most rigorous testing processes available.
Side effects are generally mild. Of the noted finasteride side effects, the most common are erectile dysfunction, a reduced level of interest in sex, and ejaculation issues. Although other side effects can occur, they’re uncommon and, for most men, cease to occur when they stop taking finasteride.
There are things you can do to reduce the side effects of finasteride, including staying consistent with your dosage and when you take your medication, storing finasteride properly. Keeping an open line of communication with your healthcare provider to discuss any potential side effects as soon as you notice them can also be very helpful.
If you’re starting to notice the early signs of hair loss and want to take action, taking finasteride can be an effective way to maintain the hair you have and stimulate growth in the areas of your scalp that are affected by male pattern baldness.
We offer finasteride online, either by itself or with minoxidil (the active ingredient in Rogaine®) in our Hair Power Pack or in our topical finasteride and minoxidil spray.
You can also explore other options for protecting and restoring your hair in our complete range of hair loss treatments. If you’re interested in using finasteride, you can learn more about what to expect in our guide to the typical finasteride results timeline.
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