Going bald sucks. Finasteride does not. Millions of men use it every year to help them keep the hair they have and maybe even re-grow a lil bit of what they've lost.
Finasteride, the active ingredient in Propecia®, is an oral medication that’s designed to treat and prevent male pattern baldness. It was approved by the FDA to treat benign prostatic hyperplasia in 1992, and as a treatment for male pattern baldness in 1997.
Along with minoxidil, it’s one of two evidence-backed medications proven to help you keep and maintain your hair. In some cases, using finasteride could also help you regrow hair in areas of your scalp that have been affected by hair loss.
As an oral medication, it's sold in two different forms: finasteride 1mg tablets and finasteride 5mg tablets.
Below, we've discussed what both finasteride 1mg and 5mg are used for, how they work and which one might be best for you.
We’ve also covered the main differences between the 1mg and 5mg finasteride tablets that are available, along with information on which option is best for you.
Before we get into the nitty gritty of how these two common finasteride doses compare, here’s a quick look at what makes them unique.
Finasteride is in a class of medications called 5-alpha reductase inhibitors, or 5α-reductase inhibitors. They work by inhibiting the effects of an enzyme known as 5-alpha reductase, which converts testosterone into dihydrotestosterone (DHT), a hormone responsible for male pattern hair loss.
5-alpha reductase blockers reduce DHT levels, slowing down, stopping, or reversing the effects of male pattern baldness. They can also encourage hair regrowth and increase hair count.
Research shows that a typical dose of finasteride reduces DHT levels in your blood by as much as 70 percent compared with a placebo.
It can also reduce DHT levels by 90 percent in your prostate gland, which can effectively treat androgenic alopecia and an enlarged prostate.
The typical finasteride dosage for hair loss is 1mg per day, but your healthcare provider will decide what’s best for you. Most hair loss treatments containing finasteride use this dose, including the original 1mg Propecia tablets.
Research backs this up. In one study, 80 percent of men saw improvements after using 1mg finasteride for 12 months to treat male pattern hair loss.
Another older study found that 83 percent of men maintained their hair after two years on 1mg finasteride compared to just 28% on a placebo.
But here's the thing: More finasteride isn’t necessarily better. For hair loss, 1mg of finasteride per day is enough. Taking more won’t improve results and could increase your risk of side effects.
When should men consider a higher dose of finasteride? While the 1mg dose of finasteride is effective for hair loss treatment, the 5mg dose targets prostate-related issues.
Typically, the 5mg dose of finasteride is prescribed for benign prostatic hyperplasia (BPH), or enlarged prostate.
BPH is a non-cancerous condition that can make urination difficult due to prostate enlargement pressing against the urethra. Nearly all men will eventually experience BPH at some point in their lives.
The 5mg finasteride dose for BPH, often sold under the brand name Proscar®, helps control prostate growth and ease BPH symptoms, like trouble urinating.
Remember, thisdosage of finasteride is not for hair loss.
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Finasteride is generally safe and doesn’t interact with other drugs. However, like all prescription medications, it can have potential side effects.
Fortunately, less than two percent of men report these issues, suggesting a low overall risk.
Possible adverse events include:
Skin rashes
Fatigue
Dizziness
Headaches
Swelling in the lips and face
Breast swelling or nipple discharge
The most common side effects are sexual health-related, like decreased libido, erectile dysfunction (ED), and ejaculation disorder.
Here’s how these possible sexual side effects vary based on dosage:
Potential side effects of finasteride at a 1mg dose include:
Decreased sex drive
Erectile dysfunction (ED)
Serious side effects from finasteride treatment are highly uncommon, especially with the smaller dose. And decreased libido — the most common side effect of finasteride — only affects 1.8 percent of men who take it.
Compared to the 1mg dose, finasteride 5mg has a few more noticeable side effects.
In clinical trials, eight percent of men on finasteride 5mg experienced ED, six percent of men reported reduced interest in sex, and just under four percent noticed decreased ejaculation volume.
Other side effects reported by men using finasteride 5mg include:
Rash
Breast tissue enlargement
Breast tissue tenderness
While discontinuation of both lower and higher doses of finasteride due to sexual dysfunction is rare, it does happen. Finasteride and Prostate Cancer Risks
Finasteride has been shown to lower the overall risk of prostate cancer. However, some old research from 1993 suggested it might increase the risk of high-grade prostate cancer.
These earlier findings are now believed to due to detection bias and other factors. Today, the scientific consensus is that finasteride is safe hair loss treatment for most men.
A 2019, study involving 10,000 participants found no link between finasteride and an elevated risk of prostate cancer.
For more details on finasteride’s side effects and guidance on what to do if you experience any, check out our full guide to the side effects of finasteride.
For men pursuing hair restoration, finasteride is usually taken as a pill, but it can also be applied directly to the hair and scalp.
Topical finasteride isn’t yet FDA-approved yet, scientists are working on it. Recent clinical studies show that topical finasteride is just as effective as oral finasteride, but might be safer.
Though it can cause skin irritation like many topical treatments, topical finasteride has less of an impact on your body overall.
Trials reveal that the concentration in your bloodstream is over 100 times lower with topical finasteride vs. the oral version.
Because it’s not cycling through your entire system, it affects fewer organs and tissues.
Finasteride comes in 1mg or 5mg tablets. For male pattern baldness, stick to the 1mg dose daily, or follow a healthcare professional’s advice.
Here’s a recap of what to know about 5mg finasteride vs 1 mg:
It’s effective. Finasteride works. Just 1 mg of finasteride is proven to effectively treat male pattern baldness. You’ll typically see results within 3-6 months, and with consistent use, most men retain the majority of their hair even two years later.
Combined treatment might be more powerful. Finasteride is even more effective for male hair loss when combined with minoxidil. Curious about this option? Talk to a healthcare professional.
More isn’t better. When taking finasteride for hair loss, a higher dosage won’t reduce the severity of your hair loss, improve hair growth, or speed up your results. But it may increase your risk of sexual side effects, so we strongly recommend saving the 5mg dose for BPH needs.
If your goal is ditching hair loss for good, check out our wide range of proven hair loss treatments for men, including FDA-approved medications like finasteride and minoxidil.
Try our Saw Palmetto shampoo, formulated to help thicken hair, our combination minoxidil and finasteride spray, or our Hair Power Pack — which includes several of our best hair loss treatment products for men.
When you’re ready to connect with a licensed healthcare provider, take our free online quiz to get started.
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