When scientists look at how saw palmetto affects the body, particularly blood pressure, they’ve found some interesting but limited information. Most research has actually focused on how saw palmetto helps with prostate problems, especially something called enlarged prostate (BPH) or hair loss. Blood pressure effects were usually just something researchers happened to notice while studying these other conditions, rather than being the main focus.
A large medical review published in the Journal of the American Medical Association in 2021 looked at many different studies of saw palmetto. After examining thousands of people who took the supplement, there wasn’t any clear evidence that it either raised or lowered blood pressure.
One of the biggest and most careful studies ever done on saw palmetto was called the CAMUS trial. In this study, researchers kept close track of people’s blood pressure while they were taking either saw palmetto or a placebo (sugar pill). What they found was that there wasn’t any meaningful difference in blood pressure between the two groups.
To understand why saw palmetto doesn’t seem to affect blood pressure much, it helps to know how it works in the body. It mainly affects certain hormones and enzymes related to prostate health. It doesn’t directly interact with the body’s main systems that control blood pressure – like the kidney hormone system (called renin-angiotensin-aldosterone) or the nervous system’s control of blood pressure.
Some scientists have suggested that saw palmetto might indirectly affect blood pressure because it has mild anti-inflammatory properties. While we know that inflammation can affect heart health and blood pressure, saw palmetto’s anti-inflammatory effects appear to be too mild to cause noticeable changes in most people’s blood pressure.
It’s worth mentioning that while large studies haven’t shown direct effects on blood pressure, there have been occasional reports of individuals experiencing blood pressure changes while taking saw palmetto. However, these reports are few and far between, and when scientists tried to confirm these effects in larger, controlled studies, they couldn’t replicate the results. The blood pressure changes in these cases might have been due to other factors, like other medications, existing health conditions, or just normal changes in blood pressure that happen throughout the day.
Most healthcare providers consider saw palmetto pretty safe when it comes to blood pressure, especially when people take the standard dose of 320mg per day or less. This conclusion comes from both scientific studies and years of people using it. However, this doesn’t mean you shouldn’t be careful – it’s still important to monitor your blood pressure when starting any new supplement, especially if you have heart problems or take blood pressure medications.
The German Commission E, which is like Germany’s FDA for herbal medicines, has also reviewed saw palmetto and found it doesn’t significantly affect the heart or blood pressure when used correctly.
One limitation to keep in mind is that most studies on saw palmetto have only lasted a few months to a few years. We don’t know as much about what might happen with very long-term use. Also, different brands of saw palmetto can vary quite a bit in quality and strength, which might affect how well they work or what side effects they might have.
Drug Interactions
When it comes to saw palmetto and drug interactions, we need to be especially careful with several types of medications:
Blood Pressure Medications: Saw palmetto might interact with blood pressure medicines, though the evidence isn’t strong. If you’re taking medications like:
- ACE inhibitors (like lisinopril)
- Beta blockers (like metoprolol)
- Calcium channel blockers (like amlodipine)
- Diuretics (water pills)
It’s important to have your blood pressure checked regularly and tell your doctor you’re taking saw palmetto. While serious interactions are rare, even small changes in blood pressure could be important if you’re already on these medications.
Blood Thinners: This is one of the more important potential interactions to know about. If you’re taking medications like:
- Warfarin (Coumadin)
- Aspirin
- Clopidogrel (Plavix)
Saw palmetto might increase their blood-thinning effects. This is because saw palmetto may have a mild effect on blood clotting itself. While this effect is usually small, when combined with blood thinners, it could potentially increase your risk of bleeding. If you notice any unusual bruising or bleeding, you should contact your healthcare provider right away.
Hormone-Related Medications: Because saw palmetto affects hormone pathways in the body, it might interact with:
- Testosterone replacement therapy
- Finasteride (Proscar, Propecia)
- Birth control pills
The herb works similarly to some prostate medications, so taking them together could either increase side effects or interfere with how well the medications work.
Liver-Metabolized Medications: Saw palmetto is processed by the liver, just like many medications. This means it might affect how quickly your body processes certain drugs. The technical term for this is “cytochrome P450 pathway interactions.” In everyday terms, this means:
- The herb might make some medications leave your system faster or slower than usual
- This could make medications either less effective or cause them to build up in your body
- The effect is usually mild, but it’s something to be aware of
Precautions
Timing Matters
- Try to take saw palmetto at a different time than your other medications
- This can help reduce the chance of interactions
- Ask your pharmacist about the best timing for your specific medications
Monitoring
- Keep track of any new symptoms or changes when you start taking saw palmetto
- Regular blood pressure checks are important if you’re on blood pressure medications
- Watch for any unusual bleeding or bruising if you’re on blood thinners
- Pay attention to any changes in how your regular medications seem to be working
Communication
- Always tell your healthcare providers about ALL supplements you’re taking
- This includes saw palmetto and any other herbs or vitamins
- Keep a list of everything you take to share at medical appointments
- Don’t start or stop saw palmetto without telling your healthcare provider if you’re on prescription medications
Special Situations
- If you’re scheduled for surgery, you should stop taking saw palmetto at least 2 weeks before
- This is because of the potential bleeding risk
- Tell your surgeon and anesthesiologist that you’ve been taking it
- The same applies for dental surgery or any invasive procedures
Remember: While these interactions are possible, many people take saw palmetto safely along with other medications. The key is being informed and working with your healthcare providers to monitor any potential issues. They might need to:
- Adjust your medication doses
- Change the timing of when you take things
- Monitor you more closely with blood tests
- Suggest alternatives if the risk of interactions is too high
Evidence Based Conclusions
Saw palmetto appears to have minimal direct effect on blood pressure for most users when taken at standard doses. It is generally considered safe from a cardiovascular perspective though individual responses may vary. Much more research is needed for definitive conclusions.
Recommendations:
- Monitor blood pressure when starting supplementation.
- Consult healthcare providers if taking blood pressure medications.
- Consider starting with lower doses to assess individual response.
- Discontinue use if notable blood pressure changes occur.
Given the limited direct research on saw palmetto’s blood pressure effects, individuals with blood pressure concerns should approach its use cautiously and with medical supervision. While serious blood pressure effects appear rare, individual responses can vary, and monitoring is prudent, especially when first starting the supplement.
