Are ginseng or ginkgo biloba associated with hypertension (high blood pressure)?

Ginseng and Blood Pressure

Ginseng at high doses is associated with elevation of blood pressure and should be avoided or used cautiously in patients with hypertension, while ginkgo biloba has a neutral effect on blood pressure and is not associated with hypertension.

Ginseng and Hypertension

The 2020 International Society of Hypertension guidelines explicitly list ginseng at high doses among herbal substances that can increase blood pressure 1. This classification places ginseng alongside other known blood pressure elevators including ma-huang, licorice, St. John's wort, and yohimbine 1, 2.

Key Clinical Considerations for Ginseng:

• The blood pressure effect is dose-dependent, with high doses being problematic 1, 2
• Individual variability is substantial, with greater blood pressure increases occurring in elderly patients, those with higher baseline blood pressure, patients already on antihypertensive therapy, or those with kidney disease 1, 2
• Screen all hypertensive patients for ginseng use as part of routine assessment 1, 2

Research Evidence on Ginseng:

The research literature shows mixed findings, which explains why guidelines specify "high doses" as problematic:

• A 2005 randomized controlled trial found that North American ginseng (3g) exerted a neutral acute effect on blood pressure in 16 hypertensive individuals over 160 minutes 3
• A 2016 systematic review and meta-analysis of 17 studies (n=1,381) found no significant overall effect of ginseng on systolic, diastolic, or mean arterial blood pressure 4
• However, the same meta-analysis revealed a significant association between body mass index and treatment differences, suggesting certain populations may be more susceptible 4
• A 1992 study showed systolic blood pressure decreased significantly with both low-dose (60mg ginkgo + 100mg ginseng) and high-dose (120mg ginkgo + 200mg ginseng) administration 5

The apparent contradiction between guideline warnings and some neutral research findings likely reflects dose-dependent effects, variable ginsenoside content in different preparations, and individual patient susceptibility 1, 4.

Ginkgo Biloba and Blood Pressure

Ginkgo biloba is NOT associated with blood pressure elevation and does not appear in hypertension guideline tables of substances that raise blood pressure 1.

Research Evidence on Ginkgo Biloba:

• The definitive Ginkgo Evaluation of Memory (GEM) study followed 3,069 elderly participants (mean age 79 years) for a median of 6.1 years and found no effect of ginkgo biloba (240mg/day) on blood pressure changes, pulse pressure, or incident hypertension 6
• The hazard ratio for incident hypertension was 0.99 (95% CI 0.84-1.15), indicating no increased risk 6
• Baseline hypertension status did not modify any effects of ginkgo biloba 6

Important Caveat About Ginkgo Biloba:

While ginkgo biloba does not elevate blood pressure, the 2006 National Stroke Association guidelines note that ginkgo biloba may alter bleeding time and should not be used concomitantly with warfarin due to bleeding risk 1. This is a separate safety concern unrelated to blood pressure.

Clinical Management Algorithm:

For patients with hypertension or at risk for hypertension:

1. Screen for ginseng use at every visit, specifically asking about dose and frequency 1, 2
2. If using high-dose ginseng: Consider reducing or eliminating it, particularly in elderly patients, those with uncontrolled hypertension, or those on antihypertensive medications 1, 2
3. If ginseng is preferred by the patient: Treat blood pressure to target regardless, with more frequent monitoring and potential adjustment of antihypertensive therapy 1, 2
4. Ginkgo biloba use: Does not require modification for blood pressure concerns, but assess for anticoagulant interactions 1, 6