Saw Palmetto vs Finasteride (2026): Prostate, Hair Loss and Side Effects Compared

At a Glance

• Enlarged prostate (BPH) Finasteride 5 mg cut the risk of BPH surgery by 55% and urinary retention by 57% over 4 years⁶. Saw palmetto made little to no difference vs placebo in the 2023 Cochrane review¹.
• Hair loss In a 2-year study of 100 men, 68% improved on finasteride 1 mg vs 38% on saw palmetto 320 mg⁹.
• Side effects Finasteride caused more decreased libido, erection problems and ejaculation problems than placebo⁵. Saw palmetto’s side effects were mild and similar to placebo¹¹².
• PSA Finasteride roughly halves PSA, so doctors double the reading⁷. Saw palmetto doesn’t appear to change PSA².
• Top pick NOW Saw Palmetto Extract 320 mg – for men who still want to try saw palmetto: 320 mg of extract standardized to 85–95% fatty acids, from our guide to the best pumpkin seed oil with saw palmetto supplements.

The Short Answer: Finasteride works better than saw palmetto, for both an enlarged prostate and hair loss. It shrinks the prostate, lowers the risk of surgery and urinary retention⁵⁶, and helped nearly twice as many men regrow hair in a head-to-head study⁹. Saw palmetto didn’t beat placebo for prostate symptoms in the best trials¹³⁴.

On this page

1. How Each One Works
2. Saw Palmetto vs Finasteride at a Glance
3. For an Enlarged Prostate (BPH)
4. For Hair Loss
5. Side Effects
6. PSA and Prostate Cancer Screening
7. Can You Take Saw Palmetto and Finasteride Together?
8. Which Is Right for You?
9. Final Verdict
10. Frequently Asked Questions

Saw palmetto’s main advantage is tolerability: it has few side effects and doesn’t affect PSA tests²¹². Finasteride is a prescription drug, so talk to your doctor about whether it’s right for you. If you want to compare saw palmetto products, see our guide to the best pumpkin seed oil with saw palmetto supplements.

How Each One Works

Both target 5-alpha reductase, the enzyme that turns testosterone into DHT, a hormone linked to prostate growth and male-pattern hair loss. Finasteride is a prescription drug that blocks this enzyme⁵. Saw palmetto is thought to act on the same enzyme¹¹, but it hasn’t matched finasteride’s results¹⁹. For more on the mechanism, see how saw palmetto blocks DHT and natural vs prescription DHT blockers.

Saw Palmetto vs Finasteride at a Glance

	Finasteride	Saw palmetto
Prostate symptoms	Improved vs placebo56	Little to no difference vs placebo1
Prostate size	Down 19% in 1 year5	No change vs placebo3
Surgery or urinary retention	Risk cut by 55–57% over 4 years6	Not shown
Male-pattern hair loss	68% improved in 2 years9	38% improved in 2 years9
PSA	Roughly halved7	No meaningful change2
Sexual side effects	More than placebo5	Side effects overall mild and similar to placebo112
Availability	Prescription	Over the counter

For an Enlarged Prostate (BPH)

Finasteride

In a 1-year trial of 895 men, finasteride 5 mg a day lowered symptom scores, improved urine flow by 22% and shrank the prostate by 19% (vs 3% on placebo)⁵. The 4-year PLESS trial in 3,040 men found finasteride reduced the need for surgery from 10% to 5% and acute urinary retention from 7% to 3%⁶.

Saw Palmetto

The 2023 Cochrane review of 27 studies found saw palmetto makes little to no difference to urinary symptoms or quality of life compared with placebo¹. Two large US trials, STEP and CAMUS, found no benefit, even at three times the usual dose³⁴. See our full guide to saw palmetto for BPH.

Why Some Sites Say They’re Equal

A 2002 Cochrane review found saw palmetto produced similar improvements to finasteride in 2 comparison trials, with fewer side effects⁸. That review included combination products and trials with other drugs. The 2023 update narrowed the question to placebo comparisons and found little to no benefit¹. Some websites still quote the older review.

Our Top Saw Palmetto Pick

NOW Saw Palmetto Extract 320 mg

320 mg extract85–95% fatty acids1 softgel a day

For men who prefer to try saw palmetto first, after talking to their doctor. NOW gives 320 mg of extract standardized to 85–95% fatty acids, the dose used in the 2-year comparison with finasteride, in one softgel. It’s the best standardized extract in our guide to the best pumpkin seed oil with saw palmetto supplements. It isn’t a substitute for finasteride.

Check price on Amazon → See all 7 picks

For Hair Loss

In a 2-year open-label study, 100 men with mild to moderate male-pattern hair loss took finasteride 1 mg or saw palmetto 320 mg a day. Hair growth improved in 68% on finasteride and 38% on saw palmetto. The authors observed that finasteride worked on both the front and crown, while saw palmetto worked mainly on the crown⁹. The study had no placebo group and wasn’t blinded. For more, see our guide to saw palmetto for hair loss.

Side Effects

Finasteride

In the 1-year BPH trial, side effects were similar to placebo except for more decreased libido, impotence and ejaculation problems⁵. Some men report sexual, mental or physical symptoms that last after stopping finasteride, called post-finasteride syndrome. Whether and how often it happens is still debated¹⁰.

Saw Palmetto

A 2009 systematic review found saw palmetto’s side effects were mild and similar to placebo, most often stomach pain, diarrhea, nausea, tiredness, headache, decreased libido and runny nose¹². A 2026 case series described lasting sexual and mood symptoms in some men after saw palmetto, but the cases came from an online forum for people with post-finasteride syndrome, so it can’t show how common this is¹¹. See our full guide to saw palmetto side effects.

PSA and Prostate Cancer Screening

Finasteride lowers PSA. After 6 months or more, doctors double the PSA reading to compare it with normal ranges⁷. Saw palmetto doesn’t appear to change PSA, even at higher doses². Tell your doctor about either one before a PSA test.

Can You Take Saw Palmetto and Finasteride Together?

We didn’t find good trials of the combination. Both act on the same enzyme, and in the 2026 case series, men who combined them had more severe and longer-lasting symptoms¹¹. Don’t combine them without talking to your doctor.

Which Is Right for You?

• Finasteride has much stronger evidence for both an enlarged prostate and hair loss⁵⁶⁹. It needs a prescription and carries a risk of sexual side effects⁵.
• Saw palmetto is well tolerated and doesn’t affect PSA², but the best evidence shows it doesn’t help prostate symptoms much¹, and it’s weaker for hair loss⁹.
• See a doctor before choosing either one, especially for urinary symptoms, which can have other causes.

Final Verdict

Finasteride beats saw palmetto on effectiveness for both BPH and hair loss. Saw palmetto’s appeal is its mild side effects and lack of effect on PSA, not its results. If you’re weighing the two, have that conversation with your doctor.

If you still want to try saw palmetto, use the studied 320 mg dose, such as NOW Saw Palmetto Extract 320 mg. For the broader picture, see saw palmetto benefits.

Important: This guide is for general information and isn’t medical advice. Don’t start, stop or combine finasteride and saw palmetto without talking to your doctor.

Frequently Asked Questions

Sources & History12 sources · updated November 12, 2026

References

1. Serenoa repens for the Treatment of Lower Urinary Tract Symptoms Due to Benign Prostatic Enlargement — Cochrane Database of Systematic Reviews, 2023
2. Saw Palmetto: Usefulness and Safety — National Center for Complementary and Integrative Health
3. Saw Palmetto for Benign Prostatic Hyperplasia — New England Journal of Medicine, 2006
4. Effect of Increasing Doses of Saw Palmetto Extract on Lower Urinary Tract Symptoms: A Randomized Trial — JAMA, 2011
5. The Effect of Finasteride in Men With Benign Prostatic Hyperplasia — New England Journal of Medicine, 1992
6. The Effect of Finasteride on the Risk of Acute Urinary Retention and the Need for Surgical Treatment Among Men With Benign Prostatic Hyperplasia — New England Journal of Medicine, 1998
7. The Effect of Finasteride on Prostate Specific Antigen: Review of Available Data — Journal of Urology, 1996
8. Serenoa repens for Benign Prostatic Hyperplasia — Cochrane Database of Systematic Reviews, 2002
9. Comparative Effectiveness of Finasteride vs Serenoa repens in Male Androgenetic Alopecia: A Two-Year Study — International Journal of Immunopathology and Pharmacology, 2012
10. Post-Finasteride Syndrome: A True Clinical Entity? — International Journal of Impotence Research, 2025
11. Can We Identify a Post-Serenoa Syndrome (PSS)? A Case Series on Sexual and Psychiatric Side Effects of Serenoa repens — British Journal of Clinical Pharmacology, 2026
12. Serenoa repens (Saw Palmetto): A Systematic Review of Adverse Events — Drug Safety, 2009

Update history

• November 12, 2026Rewritten with a side-by-side table covering BPH, hair loss, PSA and side effects; added PLESS surgery and retention figures, the 2-year hair loss comparison and the post-finasteride syndrome debate; replaced ScienceDirect links with PubMed records; removed the unsourced claim that saw palmetto has no link to sexual side effects.