Abstract
Background/Significance: As complementary and integrative therapies expand worldwide nurses and advanced practice providers increasingly encounter patients using natural products that may influence procedural safety. Mistletoe extract (Viscum album), widely used in integrative oncology, remains poorly studied in relation to anesthetic pharmacology. With rising variability in sedation responsiveness, improving global pharmacology literacy is essential to support safe cancer care.
Purpose: To describe a case of mistletoe-associated anesthetic resistance and examine mechanisms through which integrative oncology therapies may alter anesthetic effectiveness, with implications for nursing practice.
Case: A 32-year-old woman with metastatic colorectal cancer received three months of intravenous and subcutaneous mistletoe therapy. During two procedures—colonoscopy and CT-guided lung biopsy—she exhibited marked resistance to midazolam, fentanyl, and propofol. Despite escalating doses, she remained awake, interactive, and hypertensive, requiring conversion to general anesthesia. She had no substance use, opioid tolerance, or prior anesthetic concerns, and the onset of resistance coincided with mistletoe therapy.
Results: Mistletoe lectins trigger IL-1, IL-6, and TNF-α release, cytokines associated with upregulation of CYP3A4, CYP2D6, and P-glycoprotein. These pathways can accelerate anesthetic metabolism and reduce circulating drug levels. Experimental findings also suggest modulation of μ-opioid and GABA-A receptors, potentially lowering receptor affinity and decreasing sedative and analgesic effects. These mechanisms offer a plausible explanation for awareness despite appropriate dosing.
Nursing & Global Practice: This case highlights the need for nurses to strengthen competencies in pharmacology and integrative health. Routine perioperative screening for herbal and natural products is essential, especially in settings where complementary therapies are common. Advanced practice nurses can lead safety initiatives, enhance education on herb–drug interactions, and support culturally informed assessment.
Conclusion: This may represent one of the earliest documented cases of mistletoe-related anesthetic resistance. Understanding mistletoe’s potential to alter anesthetic metabolism and receptor responsiveness is vital to preventing subtherapeutic sedation and intraoperative awareness. Further research and global perioperative guidance on integrative oncology therapies are needed.
Notes
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Sigma Membership
Non-member
Type
Presentation
Format Type
Text-based Document
Study Design/Type
Case Study/Series
Research Approach
Qualitative Research
Keywords:
Acute Care, Teaching and Learning Strategies, Instrument and Tool Development, Anesthesia, Drug Side Effects, Herbal Medicine, Drug-Herb Interactions
Recommended Citation
Murphy, Erin Elizabeth and Molina, Maria R., "Anesthetic Resistance Linked to Mistletoe Therapy: Implications for Herb–Drug Interactions" (2026). International Nursing Research Congress (INRC). 290.
https://www.sigmarepository.org/inrc/2026/presentations_2026/290
Conference Name
37th International Nursing Research Congress
Conference Host
Sigma Theta Tau International
Conference Location
Toronto, Ontario, Canada
Conference Year
2026
Rights Holder
All rights reserved by the author(s) and/or publisher(s) listed in this item record unless relinquished in whole or part by a rights notation or a Creative Commons License present in this item record. All permission requests should be directed accordingly and not to the Sigma Repository. All submitting authors or publishers have affirmed that when using material in their work where they do not own copyright, they have obtained permission of the copyright holder prior to submission and the rights holder has been acknowledged as necessary.
Review Type
Abstract Review Only: Reviewed by Event Host
Acquisition
Proxy-submission
Date of Issue
2026-09-23
Anesthetic Resistance Linked to Mistletoe Therapy: Implications for Herb–Drug Interactions
Toronto, Ontario, Canada
Background/Significance: As complementary and integrative therapies expand worldwide nurses and advanced practice providers increasingly encounter patients using natural products that may influence procedural safety. Mistletoe extract (Viscum album), widely used in integrative oncology, remains poorly studied in relation to anesthetic pharmacology. With rising variability in sedation responsiveness, improving global pharmacology literacy is essential to support safe cancer care.
Purpose: To describe a case of mistletoe-associated anesthetic resistance and examine mechanisms through which integrative oncology therapies may alter anesthetic effectiveness, with implications for nursing practice.
Case: A 32-year-old woman with metastatic colorectal cancer received three months of intravenous and subcutaneous mistletoe therapy. During two procedures—colonoscopy and CT-guided lung biopsy—she exhibited marked resistance to midazolam, fentanyl, and propofol. Despite escalating doses, she remained awake, interactive, and hypertensive, requiring conversion to general anesthesia. She had no substance use, opioid tolerance, or prior anesthetic concerns, and the onset of resistance coincided with mistletoe therapy.
Results: Mistletoe lectins trigger IL-1, IL-6, and TNF-α release, cytokines associated with upregulation of CYP3A4, CYP2D6, and P-glycoprotein. These pathways can accelerate anesthetic metabolism and reduce circulating drug levels. Experimental findings also suggest modulation of μ-opioid and GABA-A receptors, potentially lowering receptor affinity and decreasing sedative and analgesic effects. These mechanisms offer a plausible explanation for awareness despite appropriate dosing.
Nursing & Global Practice: This case highlights the need for nurses to strengthen competencies in pharmacology and integrative health. Routine perioperative screening for herbal and natural products is essential, especially in settings where complementary therapies are common. Advanced practice nurses can lead safety initiatives, enhance education on herb–drug interactions, and support culturally informed assessment.
Conclusion: This may represent one of the earliest documented cases of mistletoe-related anesthetic resistance. Understanding mistletoe’s potential to alter anesthetic metabolism and receptor responsiveness is vital to preventing subtherapeutic sedation and intraoperative awareness. Further research and global perioperative guidance on integrative oncology therapies are needed.
Description
Mistletoe therapy may contribute to anesthetic resistance through cytokine-driven metabolic upregulation and receptor modulation. Strengthened nursing pharmacology literacy and routine screening for integrative therapies are essential for safe perioperative care. Objectives: identify mechanisms of altered anesthetic metabolism, recognize signs of resistance and herb–drug risks, and integrate comprehensive screening into global assessments.