Paweł Radkowski, Sebastian Such, Michał Żuraw, Joanna Kostrzewa, Łukasz Grabarczyk

Herbal Preparations Interactions with Drugs Used in Anesthesiological Practice

 

2026-01-30

Research subject. The objective of this review was to comprehensively identify and evaluate interactions between herbal preparations and pharmacological agents employed in anesthetic practice, with particular emphasis on opioids (e.g., fentanyl), sedative agents (propofol, thiopental, midazolam, ketamine), and skeletal muscle relaxants.

Aim of study. The topic discussed in this work is extremely important because herbal-drug interactions in anesthesiology may prolong sedation, prolong neuromuscular block, or cause bleeding. Predicting these effects remains challenging due to the frequent underreporting of herbal supplement use by patients. The consequences of combining the plant-derived substances discussed here with drugs used in anesthesiology depend on the dose and frequency of the herbal supplement, as well as on the interval between its last administration and the delivery of the anesthetic.

Materials and methods. Pharmacokinetic and pharmacodynamic mechanisms were analyzed, including modulation of cytochrome P450 enzymes, phase II enzymes – UGT, membrane transporters, and the GABA_A receptor, as well as effects on hemostasis.

Results. It has been shown that ginseng root, turmeric rhizome, green tea leaves, and many other herbal preparations described in this paper may disturb hemostasis, increasing the risk of bleeding in the perioperative period, especially with the concomitant use of anticoagulants. However, no significant interactions with propofol were identified. This is attributed to its metabolism bypassing the major CYP450 isoforms. Regardless, potential synergistic effects with cannabidiol and linalool have been described. For ketamine, thiopental, and also skeletal muscle relaxants, possible modulation of effects has been demonstrated following the administration of herbal preparations that influence key proteins responsible for the metabolism of drugs or endogenous compounds, which may result in altered duration of anesthesia. Several clinically relevant interactions were also identified. Notably, the active compounds in St. John's wort have been shown to induce CYP3A4, potentially reducing the bioavailability of midazolam. Moreover, various herbal remedies capable of modulating GABA_A receptors – such as valerian rhizomes and roots, passionflower, lemon balm leaves, and hop cones – may potentiate sedative effects.

Conclusions. In summary, a comprehensive interview regarding patients’ use of herbal preparations should constitute an integral part of preoperative assessment. Discontinuation of such products for an appropriate period prior to surgery is strongly recommended to minimize the risk of adverse herb–drug interactions in anesthetic practice.

Keywords: drug interactions, herbal preparations, anesthesiology, cytochrome P450, hemostasis.

© Farm Pol, 2025, 81(7): 439–449