Saw palmetto extract
Saw palmetto extract is an extract of the fruit of the  saw palmetto. It is marketed as a dietary supplement that may help with benign prostatic hyperplasia, but there is no clinical evidence that it is effective for this purpose.

Uses and research 
Saw palmetto extract is commonly sold as a dietary supplement intended to improve symptoms of benign prostatic hyperplasia (BPH)—also called prostate gland enlargement—which is a common condition among men as they age. An enlarged prostate may cause increased frequency or urgency of urination, difficulty initiating urination, weak urine stream or a stream that stops and starts, dribbling at the end of urination, and inability to completely empty the bladder.

Saw palmetto extract has been studied in clinical trials as a possible treatment for people with prostate cancer and for men with lower urinary tract symptoms associated with BPH. , there is insufficient scientific evidence that saw palmetto extract is effective for treating cancer or BPH and its symptoms.

One 2016 review of clinical studies with a standardized extract of saw palmetto (called Permixon) found that the extract was safe and may be effective for relieving BPH-induced urinary symptoms compared with a placebo.

Folk medicine
Saw palmetto was used in folk medicine to treat coughs or other disorders.

Precautions and contraindications

Children
The use of saw palmetto extract is not recommended in children under 12 years old because it may affect the metabolism of androgen and estrogen hormones.

Pregnancy and lactation
Saw palmetto extract should not be used during pregnancy because it may affect androgen and estrogen metabolism. As there is no rationale for using saw palmetto during pregnancy, it should be avoided when pregnant or while breastfeeding.

PSA test interference 
Saw palmetto has been shown to reduce the levels of PSA in the blood, a hormone produced by the prostate and used as a marker by healthcare providers to evaluate the presence of prostate cancer. Taking saw palmetto can artificially reduce the levels of PSA, interfering with test results.

Interactions
Saw palmetto extract has interactions with other medications. 
When used in combination with an anticoagulant or anti-platelet drug, saw palmetto extract can increase the risk of bleeding by enhancing the anticoagulation or anti-platelet effects. Some examples of anticoagulant and anti-platelet drugs include aspirin, clopidogrel, nonsteroidal anti-inflammatory drugs (NSAIDs), and warfarin.

References

5α-Reductase inhibitors
Dietary supplements
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Herbalism