Guide
Who should not take saw palmetto?
Anyone about to have surgery, taking a blood thinner, pregnant or nursing, or on a hormone-related medication should check with a doctor before taking saw palmetto — the case for caution comes from a documented bleeding event and its hormone-related mechanism, not from a specific safety trial in any of those groups.
A documented case links saw palmetto to severe bleeding during surgery, so anyone about to have a procedure, or taking a blood thinner, should check with a doctor first. The same caution applies if you're pregnant, nursing, or take a hormone-related medication, since saw palmetto's studied effect involves a hormone-processing enzyme and none of that has been tested in those situations.
Who should be cautious or check with a doctor first
- Before surgery, or if you take a blood thinner or antiplatelet medication: a 2001 case report described a patient on saw palmetto who had severe bleeding during surgery, with a prolonged bleeding time that normalized after stopping the herb. Tell a surgeon about any saw palmetto use before a scheduled procedure, and ask a doctor before combining it with a blood-thinning medication.
- Pregnancy or breastfeeding: ask a doctor before using saw palmetto if you're pregnant or nursing — there's no human safety research on saw palmetto in either situation, and its studied effect on a hormone-processing enzyme is reason enough for caution.
- Hormone-related medication (birth control, hormone therapy, or a prescription that affects the same hormone pathway): a laboratory study found a specific saw palmetto extract affects an enzyme involved in processing testosterone. No clinical trial has tested combining saw palmetto with a hormone-related medication, so ask a doctor first.
- A diagnosed kidney or liver disease: no dedicated safety study in people with kidney disease or liver disease was found, so ask a doctor before adding saw palmetto if either applies to you — that's an absence of data, not a sign that it's fine.
- Children: saw palmetto hasn't been studied in children, so it isn't something to give them without a doctor's specific guidance.
Questions people ask
Who should not take saw palmetto?
Anyone about to have surgery, taking a blood thinner, pregnant or nursing, on a hormone-related medication, or with a diagnosed kidney or liver condition should check with a doctor first, given the concerns described above.
Is saw palmetto safe for kidneys?
No dedicated study on saw palmetto in people with kidney disease was found. The broader safety review of 40 studies didn't flag a specific kidney-related harm, but that review wasn't designed to test kidney safety specifically — ask a doctor if you have a diagnosed kidney condition.
Can saw palmetto cause kidney problems?
No study we reviewed reported saw palmetto causing kidney problems, but no study specifically tested for them either. That's a gap in the research, not a confirmed answer either way.
Can saw palmetto cause liver damage?
No study we reviewed linked saw palmetto to liver damage. The systematic review of adverse events found the most serious reported events were isolated case reports of uncertain cause, and none of them described a liver-specific problem.
Who buys saw palmetto berries?
The raw berries themselves are mostly wild-harvested in Florida and bought by supplement manufacturers and extract producers, not individual consumers — nearly everyone who takes saw palmetto buys it as a finished capsule or softgel rather than the raw berry.
What shouldn't be taken with saw palmetto?
Ask a doctor before combining saw palmetto with a blood thinner, an antiplatelet medication, or a hormone-related medication. Saw palmetto and medications: what to check covers the specifics.
When to talk to a doctor
Talk to a doctor before starting saw palmetto if you're scheduled for surgery, take a blood thinner, are pregnant or nursing, take a hormone-related medication, or have a diagnosed kidney or liver condition. Saw palmetto is not a treatment for any of those situations, and nothing here is a substitute for medical care.
Related reading: saw palmetto benefits: what the research does and doesn't show, saw palmetto side effects, and saw palmetto and medications: what to check.
Sources
- Intraoperative haemorrhage associated with the use of extract of Saw Palmetto herb: a case report and review of literature A case report described one patient on saw palmetto with severe bleeding during surgery and a prolonged bleeding time that returned to normal after stopping the herb — a single case, not proof of cause, but a reason to disclose any supplement use before a procedure.
- Serenoa repens (saw palmetto): a systematic review of adverse events A systematic review of 40 studies found saw palmetto's side effects are usually mild and similar in frequency to placebo — mainly stomach upset, headache, fatigue and decreased libido — with serious events reported only in isolated case reports of uncertain cause.
- Serenoa repens (Permixon) inhibits the 5alpha-reductase activity of human prostate cancer cell lines without interfering with PSA expression A laboratory study found one specific saw palmetto extract blocked an enzyme that converts testosterone to DHT in cultured prostate cells, without lowering PSA production in those cells — a cell-culture finding, not proof it changes hormone levels in someone taking a capsule.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.