Interaction of herbal products with prescribed medications: A systematic review and meta-analysis

source extracted confidence: high 2026-04-09
#animals #biological-transport #cytochrome-p-450-enzyme-system #echinacea #herb-drug-interactions

Interaction of herbal products with prescribed medications: A systematic review and meta-analysis

Awortwe et al., 2019 | Pharmacol Res | Meta Analysis

Citation

Awortwe Charles, Bruckmueller Henrike, Cascorbi Ingolf. Interaction of herbal products with prescribed medications: A systematic review and meta-analysis. Pharmacol Res. 2019-Mar;141:397-408. doi:10.1016/j.phrs.2019.01.028

Abstract

Although several studies on pharmacokinetic and/or pharmacodynamic herb-drug interactions (HDI) have been conducted in healthy volunteers, there is large uncertainty on the validity of these studies. A qualitative review and a meta-analysis were performed to establish the clinical evidence of these interaction studies. Out of 4026 screened abstracts, 32 studies were included into the qualitative analysis. The meta-analysis was performed on eleven additional studies. St. John's wort (SJW) significantly decreased the AUC (p < 0.0001) and clearance (p = 0.007) of midazolam. Further subgroup analysis identified age to affect Cmax of midazolam (p < 0.01) in the presence of SJW. Echinacea purpurea (EP) significantly increased the clearance of midazolam (p = 0.01). Evidence of publication bias (p > 0.001) was shown on the effect of the herbal products o half-life of midazolam. Green tea (GT) showed significant 85% decrease in plasma concentration of nadolol. The study findings suggest that GT, SJW and EP perpetuate significant interactions with prescribed medications via CYP3A4 or OATP1A2. Our studies show that meta-analyses are important in the area of natural products to provide necessary information on their use in overall medication plans in order to avoid unintended interactions.

Key Findings

Our studies show that meta-analyses are important in the area of natural products to provide necessary information on their use in overall medication plans in order to avoid unintended interactions.

Outcomes Measured

  • Requires manual extraction

Population

Field Value
Population healthy volunteers
Sample Size 32
Age Range See abstract
Condition See abstract

MeSH Terms

  • Animals
  • Biological Transport
  • Cytochrome P-450 Enzyme System
  • Echinacea
  • Herb-Drug Interactions
  • Humans
  • Hypericum
  • Hypnotics and Sedatives
  • Midazolam
  • Oximes
  • Plant Preparations
  • Tea

Evidence Classification

  • Level: Meta Analysis
  • Publication Types: Journal Article, Meta-Analysis, Research Support, Non-U.S. Gov't, Systematic Review
  • Vertical: echinacea

Provenance

Source extracted via PubMed E-utilities API on 2026-04-09