Interactions

Interactions with Drugs

Saw palmetto may increase the risk of bleeding when taken with drugs that increase the risk of bleeding. Some examples include aspirin, anticoagulants (blood thinners) such as warfarin (Coumadin®) or heparin, antiplatelet drugs such as clopidogrel (Plavix®), and nonsteroidal anti-inflammatory drugs such as ibuprofen (Motrin®, Advil®) or naproxen (Naprosyn®, Aleve®). Some batches of the discontinued combination herbal preparation PC-SPES®, which contains saw palmetto and seven other herbs, has been found to contain several medications including the blood thinner warfarin.

Saw palmetto may affect blood pressure. Caution is advised in people taking drugs that may affect blood pressure.

Early research found that saw palmetto lacks effect on cytochrome P450 1A2, 3A4, 2E1, or 2D6 activity.

Saw palmetto may also interact with agents that may affect hemoglobin levels, agents that may affect the immune system, agents that may affect the liver, agents that may lower seizure threshold, agents that may regulate heart rate, agents that may treat genitourinary tract disorders, agents that may treat impotence, agents that may treat stomach disorders, antibiotics, anticancer agents, anti-inflammatories, disulfiram (Antabuse®), and hormonal agents (such as androgens or antiandrogens).

Interactions with Herbs and Dietary Supplements

Saw palmetto may increase the risk of bleeding when taken with herbs and supplements that are believed to increase the risk of bleeding. Multiple cases of bleeding have been reported with the use of Ginkgo biloba, and fewer cases with garlic. Numerous other agents may theoretically increase the risk of bleeding, although this has not been proven in most cases.

Saw palmetto may affect blood pressure. Caution is advised in people taking herbs or supplements that affect blood pressure.

Early research found that saw palmetto lacks effect on cytochrome P450 1A2, 3A4, 2E1, or 2D6 activity.

Tannins in saw palmetto may prevent iron absorption.

Saw palmetto may also interact with antibacterials, anticancer herbs and supplements, anti-inflammatories, cat's claw, echinacea, herbs and supplements that may affect hemoglobin levels, herbs and supplements that may affect the immune system, herbs and supplements that may lower seizure threshold, herbs and supplements that may regulate heart rate, herbs and supplements that may treat genitourinary tract disorders, herbs and supplements that may treat impotence, herbs and supplements that may affect the liver, herbs and supplements that may treat stomach disorders, hormonal herbs and supplements (such as androgens, antiandrogens, or phytoestrogens), Pinus pinaster, and Urtica dioica.

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

www.naturalstandard.com