Saw Palmetto Side Effects: What to Know Before You Take It

Saw palmetto comes from the berries of a palm native to the southeastern United States, and it's the most popular ingredient in men's prostate supplements. It's been studied in a number of clinical trials, which means there's a reasonable amount of safety data compared with many herbs.

Here's what that research shows about saw palmetto side effects, who should skip it, and how to lower your risk if you take it.

This article is general information, not medical advice. Talk to your doctor before starting saw palmetto, especially if you take any medication.

Common saw palmetto side effects

In clinical trials, most men taking saw palmetto had side effects at about the same rate as men taking a placebo. When side effects do show up, they're usually mild:

• Upset stomach or nausea, often when taken on an empty stomach
• Constipation or diarrhea
• Headache
• Dizziness
• Bad breath or an unpleasant taste, occasionally reported

Taking saw palmetto with food helps many people with stomach issues. If a side effect is strong or doesn't go away, stop taking it and check with your doctor.

Bleeding risk and surgery

Saw palmetto may affect the blood's ability to clot. The concern is based on limited evidence, including a case report of excessive bleeding during surgery, but drug references take it seriously:

• Stop saw palmetto at least two weeks before surgery, dental work or a medical procedure, unless your doctor says otherwise.
• Watch for signs of bleeding, like easy bruising, nosebleeds, bleeding gums, or dark or bloody stools, and tell your doctor if you notice them.
• Avoid it if you have a bleeding disorder, such as hemophilia.

Hormone-related effects

Saw palmetto appears to affect how the body processes some male hormones, which is part of why it's used for prostate health. In men, reviewers haven't found this to be a serious safety concern, but a few things are worth knowing:

• Sexual side effects. A small number of men report lower sex drive or trouble with erections. If you notice this, stop and talk to your doctor.
• Pregnancy. Because of its hormone-related effects, saw palmetto is not recommended during pregnancy or for women who may become pregnant.
• PSA testing. If you get PSA blood tests for prostate screening, tell your doctor you take saw palmetto so they have the full picture.

Saw palmetto medication interactions

Talk to your doctor or pharmacist before taking saw palmetto if you use:

• Blood thinners and anti-platelet drugs, like warfarin, heparin and clopidogrel
• Aspirin, which can add to bleeding risk
• Other supplements that affect clotting, such as garlic, ginger, ginkgo or fish oil
• Hormone medications, including estrogen, hormonal birth control, or testosterone therapy
• Prescription prostate medications, so your doctor can decide whether combining them makes sense

Who should avoid saw palmetto

• Women who are pregnant, breastfeeding or trying to get pregnant
• Anyone under 18
• Anyone taking blood thinners or with a bleeding disorder, unless their doctor approves it
• Anyone with surgery or dental work scheduled in the next two weeks
• Anyone on hormone therapy or with a hormone-sensitive condition, without a doctor's OK

Rare case reports have linked saw palmetto to liver or pancreas problems, though a direct cause wasn't proven. Stop and see a doctor right away if you notice yellowing skin or eyes, dark urine, severe stomach pain, or unusual tiredness.

How much saw palmetto is typically used?

Much of the clinical research used around 160 to 320mg a day of saw palmetto extract, often split into two doses. Products using whole saw palmetto fruit aren't always directly comparable to concentrated extracts, so milligram numbers can mean different things across brands. Follow the label, and don't take more than the directions say.

Does saw palmetto actually work?

The honest answer: the evidence is mixed. Some earlier studies were promising, but several large, well-run trials found saw palmetto did no better than a placebo for urinary symptoms in men with an enlarged prostate. It remains widely used and generally well tolerated, but it isn't a sure thing.

Other ingredients have their own research. Beta-sitosterol, for example, has some encouraging short-term studies. We compare the main prostate ingredients in our guide to the best prostate supplements, and look at two sterol-focused products in our Super Beta Prostate and ProstaGenix reviews.

Most importantly, urinary symptoms have several possible causes, so a supplement shouldn't replace a checkup. See our guides on a weak urine stream and waking up at night to pee.

How to lower your risk

• Talk to your doctor first, especially if you take medication.
• Take it with food to reduce stomach upset.
• Stick to the label dose.
• Stop two weeks before surgery or dental work.
• Choose a brand that prints its doses and is third-party tested.
• Give it time, then reassess. If you don't notice anything after two to three months, it may not be the right fit for you.

Saw palmetto in Blue Collar Nutrition Prostate

Our Prostate formula contains 200mg of saw palmetto fruit per two-capsule serving, alongside pygeum (100mg), a plant sterol complex, a three-mushroom blend of maitake, reishi and shiitake, and zinc, selenium, vitamin E and vitamin B6. Every main dose is printed on the label, and it's made in the USA with global ingredients and third-party tested. It's $34.99, or $29.74 on subscription.

The same cautions in this article apply: talk to your doctor if you take blood thinners or hormone medications, and stop it two weeks before surgery. For a broader over-40 routine, the My Prime 40+ Pack bundles Prostate with Multi Men's and your choice of Hammer or Overdrive Men's.

Frequently asked questions

What are the side effects of saw palmetto?
Most people have none. The most common are mild: upset stomach, nausea, constipation or diarrhea, headache and dizziness. Some men report lower sex drive or trouble with erections. Rarely, it may affect blood clotting.

Is saw palmetto safe to take every day?
In clinical trials, daily saw palmetto was generally well tolerated by men. Talk to your doctor first if you take blood thinners, hormone medications or prostate medications, and stop it two weeks before surgery.

Does saw palmetto cause bleeding?
It may affect blood clotting, based on limited evidence including a case report of excess bleeding during surgery. Avoid it if you have a bleeding disorder or take blood thinners without your doctor's approval, and stop it at least two weeks before surgery.

Can saw palmetto cause erectile dysfunction?
A small number of men report lower sex drive or trouble with erections while taking it. It isn't common, but if you notice it, stop taking it and talk to your doctor.

Does saw palmetto affect testosterone?
It appears to affect how the body processes some male hormones, which is part of why it's used for prostate health. Reviewers haven't found this to be a safety concern for men at typical doses. Talk to your doctor if you're on testosterone therapy.

Who should not take saw palmetto?
Women who are pregnant or trying to get pregnant, anyone under 18, anyone with a bleeding disorder or on blood thinners, anyone with surgery coming up, and anyone on hormone therapy without a doctor's approval.

What medications interact with saw palmetto?
Blood thinners like warfarin and clopidogrel, aspirin, other supplements that affect clotting, and hormone medications including estrogen and hormonal birth control. Check with your doctor or pharmacist.

How much saw palmetto should I take?
Much of the research used about 160 to 320mg a day of extract. Follow your product's label and talk to your doctor before taking more.

Does saw palmetto work?
The evidence is mixed. Some studies were promising, but several large trials found it did no better than a placebo for urinary symptoms. It isn't a substitute for seeing a doctor about urinary changes.

How much saw palmetto is in Blue Collar Nutrition Prostate?
Prostate contains 200mg of saw palmetto fruit per two-capsule serving, plus pygeum, plant sterols, a three-mushroom blend and supporting nutrients.

These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease. Consult your physician before beginning any supplement, particularly if you have a medical condition or take prescription medication.