Finasteride 1mg vs 5mg: What’s the Difference and Which Dose Is Right for You?

Key Takeaways:

• 1mg oral finasteride effectively treats hair loss and is the standard dose for male pattern baldness.

• 5mg oral finasteride is for prostate issues, not hair loss.

• Higher doses don’t improve hair loss results and may increase the risk of sexual side effects.

• Combining oral finasteride with minoxidil can further enhance hair loss treatment results for many men.
  

Let’s talk 5mg finasteride vs 1mg — two different doses, one powerful hair loss treatment.

Finasteride is an oral medication that’s used to treat and prevent male pattern baldness. It was approved by the Food and Drug Administration (FDA) back in 1992 to treat benign prostatic hyperplasia, and in 1997, it was also approved to fight hair loss.

Finasteride is one of two medications (minoxidil (Rogaine^®) is the other) proven to help men maintain their hair. Using finasteride may also help you regrow hair.

So what’s the difference between finasteride 1mg and finasteride 5mg, and which dose is right for you? Read on to find out how they work, when to use them, and which dose makes the most sense 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 dose 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 percent 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, doctors prescribe the 5mg dose to treat 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, this dose of finasteride is not for hair loss.

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 dose:

Side Effects of Finasteride 1mg

Potential side effects of finasteride at a 1mg dose include:

• Decreased sex drive

• Erectile dysfunction (ED)

• Decreased ejaculate volume

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.

Side Effects of Finasteride 5mg

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 be due to detection bias and other factors.

Today, the scientific consensus is that finasteride is a 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.

Finasteride is also available as a topical medication that you apply directly to your hair and scalp.

Topical finasteride isn’t yet FDA-approved, but scientists are working on it. Possible side effects include skin irritation, sexual and psychological impacts, and the risk of exposure to others (particularly pregnant people).

Read more about topical finasteride.

If you’re tackling hair loss, your provider will prescribe you 1mg of oral finasteride daily — it’s effective for maintaining and regrowing hair. For men with prostate concerns, 5mg finasteride is the typical dose doctors prescribe.

When you’re ready to connect with a licensed healthcare provider to talk through your hair loss treatment options, take our free online quiz to get started.

Can you use oral finasteride with other hair loss treatments?

Yes. Finasteride often works best when combined with other hair restoration treatments like minoxidil (Rogaine^®) or low-level laser therapy. Using multiple approaches can improve results and help you maintain long-term hair density.

How long does it take to see results from oral finasteride?

Most men notice reduced shedding in three to six months and visible regrowth after six to 12 months of consistent use.

What happens if I stop taking oral finasteride?

If you discontinue treatment, DHT levels return to normal, and hair loss typically resumes within three to six months.