Safety

The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Allergies

Few allergic symptoms have been reported with saw palmetto. A study of people taking the combination product PC-SPES® (no longer commercially available), which includes saw palmetto and seven other herbs, reports that three out of 70 people developed allergic reactions. In one case, the reaction included throat swelling and difficulty breathing.

Avoid in people who are allergic or sensitive to saw palmetto, any of its parts, or other members of the Arecaceae or Palmae family.

Side Effects and Warnings

Few severe side effects of saw palmetto are noted in the published scientific literature. A study found that there may be a lack of herb-drug interactions associated with saw palmetto. Overall, there appear to be few safety concerns with short-term use of saw palmetto. Saw palmetto appears to be well tolerated by most people for up to 3-5 years. LSESR, a particular extract of Serenoa repens, may be better tolerated, although this claim has not been confirmed.

The most common complaints involve the stomach and intestines, and include stomach pain, nausea, vomiting, bad breath, constipation, diarrhea, gas, heartburn, and indigestion. Stomach upset caused by saw palmetto may be reduced by taking it with food.

Some reports describe ulcers, liver damage, liver inflammation, and jaundice (yellowing of the skin), but the role of saw palmetto is not clear in these cases. Similarly, reports of headache, dizziness, insomnia, depression, chest pain, abnormal heart rhythm, heart attack, heart disease, heart failure, high or low blood pressure, respiratory tract problems (including breathing difficulties), and muscle pain have been reported but may not be clearly caused by saw palmetto.

Saw palmetto may also cause or induce bloody urine, breast tenderness or enlargement, changes in blood chemistry, eye problems, flu-like symptoms, genital or urinary problems, hot flashes, inflammation of the pancreas, low energy, menstruation, mouth or teeth problems, physical injury, sexual dysfunction (such as ejaculation problems, erectile dysfunction, impotence, or low sex drive), skeletal muscle breakdown, skin reactions, and testicular pain.

Use cautiously in people scheduled to undergo some surgeries or dental work, who have bleeding disorders, or who are taking drugs that may increase the risk of bleeding. Dosing adjustments may be necessary.

Use cautiously in people who have high blood pressure, or those taking drugs or herbs and supplements that may affect blood pressure.

Use cautiously in people who have liver disorders or those taking drugs for liver disorders.

Use cautiously in patients with hormone-sensitive conditions or in those taking hormonal agents, due to possible hormonal effects of saw palmetto.

Use cautiously in people who have stomach disorders.

Use cautiously in combination with agents that may affect hemoglobin levels. Saw palmetto may reduce levels of hemoglobin, hematocrit, red blood cells, and platelets.

Avoid saw palmetto in women who are or may potentially be pregnant, due to the risk of developmental problems in the baby and hormonal effects.

Avoid saw palmetto when breastfeeding, due to a lack of available information.

Avoid saw palmetto in children, due to a lack of available information.

Avoid in people who are allergic or sensitive to saw palmetto, any of its parts, or other members of the Arecaceae or Palmae family.

In theory, prostate-specific antigen (PSA) levels may be artificially lowered by saw palmetto, based on a proposed mechanism of action of saw palmetto (inhibition of 5-alpha-reductase). Therefore, there may be a delay in diagnosis of prostate cancer or interference with following PSA levels during treatment or monitoring in men with known prostate cancer.

The combination product PC-SPES®, which contains saw palmetto and seven other herbs, has been found to contain prescription drugs including warfarin, a blood thinner. The U.S. Food and Drug Administration (FDA) has issued a warning not to use PC-SPES® for this reason, and it is no longer commercially available.

Pregnancy and Breastfeeding

Due to limited safety data, possible hormonal activity, and the risk of developmental problems in the baby, saw palmetto extract is not recommended for women who are or may potentially be pregnant, or women who are breastfeeding. Many tinctures contain high levels of alcohol and should be avoided during pregnancy.

This evidence-based monograph was prepared by The Natural Standard Research Collaboration

www.naturalstandard.com