Medicines Q&As
Q&A 368.1
How should herbal medicines be managed in patients undergoing
surgery?
Prepared by UK Medicines Information (UKMi) pharmacists for NHS healthcare professionals
Date prepared: September 2012
Background
There are an increasing number of patients using herbal medicines and for various reasons these
patients do not always disclose herbal medicine use to medical staff (1,2,3). Herbal medicines are
often mistakenly considered to be safe because they are natural. However, herbal medicines do not
have to comply with medicines legislation and many reach the market as unlicensed herbal remedies
(4,5). For this reason the content and relative safety of herbal medicines is unpredictable and there is
limited awareness of their adverse-effects and interactions with prescribed medications (4).
This Q&A summarises information from the current literature regarding commonly used herbal
medicines and how to manage their use during the peri-operative period. It includes
recommendations on discontinuation of herbal medicines prior to elective surgery.
A review of all herbal medicines is beyond the scope of this Q&A, it is intended as a guide only and is
not intended to be exhaustive.
Answer
There is limited information regarding the use of herbal medicines and the risks during surgery and
anaesthesia (3). There are no randomised controlled trials evaluating the effects of herbal medicines
during the peri-operative period (6). There are no official standards or published guidelines on the preoperative use of herbal medicines either internationally or in the United Kingdom (UK) (7, 8, 9).
One key message is that full disclosure of herbal medicines by patients and specific pre-operative
questioning by medical staff is essential. This advice is provided by the Royal College of
Anaesthetists in the UK, the Association of Anaesthetists of Great Britain, the Medicines Healthcare
Regulatory Agency and the American Society of Anaesthesiologists (10).
There are several review articles that consider the implications of herbal medicines during perioperative care (6, 11, 12, 13, 14). They concentrate on 8 to 10 of the most commonly used herbal
medicines.
Herbal medicines may affect the peri-operative patient by having a direct pharmacological effect or by
interaction with conventional medicines (11). If the pharmacokinetics and pharmacodynamics of an
individual compound are used to make decisions regarding the management of herbal medicines in
patients undergoing surgery then recommendations for discontinuation range from 24 hours to 2
weeks (6,11,14). A more straightforward approach is to discontinue all herbal medicines 2 weeks prior
to surgery (6,11,12,13). This advice is supported by the American Society of Anaesthetists (6,13).
One review, which specifically considers the effects of complementary and alternative medicines on
coagulation, also recommends that supplements should be stopped 2 weeks before surgery (15).
The risk of bleeding in surgical patients who use herbal medicines has been highlighted recently
(16,17).
The importance of proper questioning of patients is highlighted by all of the reviews
(6,11,12,13,14,15). Education of medical practitioners, greater patient communication and integrative
research are all needed to prevent adverse effects from herbal medicines in patients undergoing
surgery.
The nine most common herbal medicines are considered below.
From the National Electronic Library for Medicines. www.nelm.nhs.uk
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Medicines Q&As
Echinacea is used for the prophylaxis and treatment of viral, bacterial and fungal infections (6,11,12).
It should be avoided before transplant surgery because it may decrease the effectiveness of
immunosuppressants (12,13). Echinacea should be discontinued as far in advance as possible for
any surgery (6) ideally 2 weeks prior to surgery (11,12)
Ephedra, also known as ma huang, is used to promote weight loss, increase energy and treat
respiratory conditions such as asthma and bronchitis (6,11,12). Adverse effects of ephedra include
increased blood pressure and it may also affect cardiovascular function leading to cardiomyopathy
(6,11,12,13). It should be discontinued at least 24 hours (6) and ideally 2 weeks prior to surgery (12).
Garlic has the potential to modify the risk of developing atherosclerosis by reducing blood pressure
and thrombus formation and lowering serum cholesterol levels (6,11,12,13). Because it has been
shown to decrease platelet aggregation it should be stopped 7 days prior to surgery especially if postoperative bleeding is a concern (6, 11). Ideally, garlic should be discontinued 2 weeks prior to surgery
(12).
Ginger is used for motion sickness and vertigo as well as post-operative nausea and vomiting, it is
also used as an anti-inflammatory (11,12,13). Ginger can cause hypoglycaemia, cardiac problems
and it may increase the risk of bleeding due to its effect on platelet function. It should be stopped 2
weeks prior to surgery (11,12)
Ginkgo is used to prevent the effects of aging, to increase energy, improve stress and improve
appetite (6,11,12). It is also used for tinnitus, vertigo, memory enhancement and sexual dysfunction
(13). It may affect platelet aggregation and should be stopped at least 36 hours prior to surgery
because of the bleeding risk (6,11). Ideally, ginkgo should be stopped 2 weeks before surgery (12).
Ginseng is used for a wide range of conditions including stress, memory loss, bleeding disorders,
appetite loss and cancer (6,11,12,13). Ginseng may cause hypoglycaemia in fasting patients and may
also cause platelet inhibition (6,11,12,13). It should be stopped at least 7 days prior to surgery (6, 11)
and ideally 2 weeks before surgery (12).
Kava is used as an anxiolytic and sedative (6,11,12,13). It can potentiate the sedative effects of
anaesthetics and should be stopped at least 24 hours prior to surgery (6) and ideally 2 weeks before
surgery (11,12).
St John’s Wort is widely used as an antidepressant. It significantly affects the metabolism of many
other drugs because it induces cytochrome P450 enzymes (6,11,12,13). The effects of many
conventional medicines including warfarin, alfentanil, midazolam and lidocaine could all be reduced
by St John’s Wort. It should be discontinued 5 to 7 days prior to surgery especially if transplant
surgery or if the patient needs warfarin post surgery (6,11). Ideally, St John’s Wort should be stopped
2 weeks prior to surgery (12).
Valerian is used for insomnia. Because it causes hypnosis, the dose should be tapered several
weeks prior to surgery (6, 11, 12). Valerian should not be stopped abruptly as it poses a risk of
withdrawal syndrome (6,11,12).
Summary



Based on the pharmacokinetics and pharmacodynamics of individual herbal medicines the
recommendations for discontinuation vary between 24 hours and 2 weeks.
It is generally advised that herbal medicines are stopped 2 weeks prior to elective surgery.
Full disclosure of herbal medicines by patients and specific pre-operative questioning by
medical staff is essential.
Limitations
There is a lack of published scientific information on the safety of herbal medicines in patients
From the National Electronic Library for Medicines. www.nelm.nhs.uk
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Medicines Q&As
undergoing surgery. The list of herbal medicines included in this review is not exhaustive, absence
from this Q&A does not imply that an herbal medicine is safe to use during the perioperative period.
Disclaimer
 Medicines Q&As are intended for healthcare professionals and reflect UK practice.
 Each Q&A relates only to the clinical scenario described.
 Q&As are believed to accurately reflect the medical literature at the time of writing.
 The authors of Medicines Q&As are not responsible for the content of external websites and
links are made available solely to indicate their potential usefulness to users of NeLM. You
must use your judgement to determine the accuracy and relevance of the information they
contain.
 This document is intended for use by NHS healthcare professionals and cannot be used for
commercial or marketing purposes.
 See NeLM for full disclaimer.
References
1. Barnes J, Anderson LA and Phillipson JD. Herbal Medicines. 2nd Edition. Pharmaceutical Press:
London. 2002 p3.
2. Collins D, Oakley S and Ramakrishnan V. Perioperative use of herbal, complementary, and over
the counter medicines in plastic surgery patients. Journal of Plastic Surgery. 2011; 11: 244-253.
3. Pass SE and Simpson RW. Discontinuation and reinstitution of medicines during the perioperative
period. American Journal of Health-Syst Pharm 2004; 61: 899-912.
4. http://www.mhra.gov.uk/Howweregulate/Medicines/Herbalmedicinesregulation/index.htm
and
http://www.mhra.gov.uk/Howweregulate/Medicines/Herbalmedicinesregulation/Licensedherbalmedicin
es/index.htm
and
http://www.mhra.gov.uk/Howweregulate/Medicines/Herbalmedicinesregulation/RegisteredTraditionalH
erbalMedicines/HowtoregisteryourproductundertheTraditionalHerbalMedicinesRegistrationScheme/Tr
aditionaluse/index.htm
accessed on 5/9/2012.
5. Javed F, Golagani A and Sharp H. Potential effects of herbal medicines and nutritional
supplements on coagulation in ENT practice. The Journal of Laryngology and Otology 2008; 122:
116-119.
6. Ang-Lee MK, Moss J and Yuan CS. Herbal medicines and perioperative care. JAMA 2001; 286 No
2: 208-216.
7. McMillan R and Taylor L. Harmless herbal medicines in day surgery? The Journal of One-Day
Surgery 2005; 15: 36-38.
8. Whelan N. Herbal medicines and surgery. Pharmacy Department. St Vincent’s University Hospital.
2003.
9. Joint Formulary Committee. British National Formulary. 63 ed. London: British Medical Association
and Royal Pharmaceutical Society of Great Britain; March 2012.
10. Hogg LA and Foo I. Management of patients taking herbal medicines in the perioperative period: a
survey of practice and policies within the anaesthetic departments of the United Kingdom. European
Journal of Anaesthesiology 2010; 27: 11-15.
11. Trapskin P and Smith KM. Herbal medications in the perioperative orthopaedic surgery patient.
Orthopaedics 2004; 27: 819-822.
12. Hodges PJ and Kam PCA. The peri-operative implications of herbal medicines. Anaesthesia
2002; 57: 889-899.
13. Sabar MD, Kaye AD and Frost EAM. Perioperative considerations for the patient taking herbal
medicines. Heart Disease 2001; 3: 87-96.
14. Whinney C. Perioperative medication management: General principles and practical applications.
Cleveland Clin J Med 2009;76: S4: S126-S132
15. Norred CL and Brinker F. Potential coagulation effects of preoperative complementary and
alternative medicines. Alternative Therapies 2001; 7: 58-67.
16. Gray S, West LM. Herbal medicines- a cautionary tale. N Z Dent J. 2012; 108:68-72
17. Wong WW et al. Bleeding risks of herbal, homeopathic, and dietary supplements. A hidden
nightmare for plastic surgeons? Aesth Surg J 2012; 32:332-46
From the National Electronic Library for Medicines. www.nelm.nhs.uk
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Medicines Q&As
Quality Assurance
Prepared by
Alison Yeo, Medicines Information Pharmacist (based on work by Emma Shepherd), South West
Medicines Information and Training. University Hospitals Bristol NHS Foundation Trust.
Date Prepared
26th September 2012
Checked by
Julia Kuczynska South West Medicines Information and Training. University Hospitals Bristol NHS
Foundation Trust.
Date of check
28th September 2012
Search strategy
Embase: [exp HERBAL MEDICINE] and [exp SURGERY] [Limit to: (Publication Types Review) and
Human, English Language]
Medline: [expHERBAL MEDICINE or exp PLANTS, MEDICINAL] and [exp SURGICAL
PROCEDURES, OPERATIVE or GENERAL SURGERY] [Limit to: Review Articles and Humans and
English Language]
Internet Search (Google Scholar Advanced Search: HERBAL MEDICINES and SURGERY)
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