Does Saw Palmetto Increase Blood Pressure And Is It Safe With Blood Pressure Medication?

Quick Answer

Saw palmetto is not known to significantly affect blood pressure (raise or lower it) and has few known drug interactions due to its lack of effect on CYP metabolizing enzymes in the liver.

Detailed Answer

Saw palmetto is a popular herbal supplement used in traditional and alternative medicine to help treat a variety of disorders, with its most common use being for benign prostatic hyperplasia (BPH).

Studies are mixed in regard to just how effective saw palmetto is for treating benign prostatic hyperplasia, and exactly how it may work. 

We do know that saw palmetto contains substances that can reduce inflammation and block the conversion of testosterone to a hormone called dihydrotestosterone (DHT), which can cause prostate growth. It may also work by slowing the growth of prostate cells by inhibiting certain growth factors and promoting cell death. 

I won't get into more about the effectiveness of saw palmetto since your question asked about blood pressure and drug interactions, so let's get into that.

Saw Palmetto & Blood Pressure

Saw palmetto is not known to affect blood pressure in any significant way.

The vast majority of studies I could find on the effects of saw palmetto supplementation that reported blood pressure as a measure generally noted no significant changes. One such study reported:

Assessments of systolic blood pressure, diastolic blood pressure, and heart rate showed small declines over the course of the study in both study groups. None of the inter-group tests of changes over time were significant.

So, if you have high blood pressure and are worried about saw palmetto making it worse, this doesn't appear to be something you need to be overly worried about.

Saw Palmetto With Valsartan

Saw palmetto extract is generally well-tolerated and is not known to have many clinically significant drug interactions.

You can view the interactions we have reported for saw palmetto on our 'drug-herbal-interaction checker', but in general, since saw palmetto isn't known to affect CYP metabolizing enzymes in the liver, it is relatively benign in regard to potential interactions.

It may interact with certain hormone-type drugs, like estrogen, and with anticoagulants, but even studies evaluating these types of interactions show they are likely only mild in severity.

There is no known interaction between it and valsartan.

Final Words

Based on the available information, it doesn't appear saw palmetto affects blood pressure significantly (i.e., doesn't increase or decrease it).

Additionally, although studies are scarce, it doesn't appear to interact with most medications, including Diovan (valsartan).

I wanted to thank you for reaching out and encourage you to do so again if anything comes up for you!