Herbal Remedies and AnaesthesiaHerbal Remedies and Anaesthesia

Adrian WONGSpecialist Registrar Anaesthetics/ITU

Wessex Deanery

Adrian WONGSpecialist Registrar Anaesthetics/ITU

Wessex Deanery

Contents• Background

• Extent of use

• Issues

• Efficacy

• Regulations

• Common herbal medicines

• Effects on anaesthesia

• Guidelines

Declaration of Interest

Foxglove (Digitalis purpurea)

Periwinkle

Purported use of herbal remedies

Asthma

Inflammatory Bowel Disease

HIV/AIDS

Psoariasis

Arthritis

Eczema Impotence

Lack of energy

Depression

Insomnia

Glands

Obesity

Cancer

Extent of Use• UK

• 4.8% of patient use

• annual expenditure - £1.6 billion

• America

• 12% general surgical

• 55% cosmetic surgery

• $27 billion

• Europe

• 40% of breast cancer patients

• 20% of lung cancer patients

• World Health Organisation

• 80% of world population

The Issues• Herbal medicines are ‘safe’

• Natural does not equal safe

• Herbal does not equal benign

• 40% of population - “safe” (MORI 2008)

• Lack of disclosure/enquiry

• Efficacy and evidence-based practice

National Institute of Medical Herbalists

The Issues• Herbal medicines are ‘safe’

• Natural does not equal safe

• Herbal does not equal benign

• 40% of population - “safe” (MORI 2008)

• Lack of disclosure/enquiry

• Efficacy and evidence-based practice

• Funding/Product regulation

regulation and licensing of herbal products

regulation and licensing of herbal products

•Lack of international consensus

•Herbal products marketed as food supplements or cosmetics

•Medicine Act 1968

• Exemption from statutory control

•EU Medicines Directive 1994

•Traditional Herbal Medicinal Products Directive (THMPD) 2004

UK legislation• Unlicensed herbal remedies

• Supplied to individual after face to face consultation

• Registered traditional herbal medicine (2005)

• Specific standards of safety and quality

• “Agreed indication based on traditional use”

• Licenced Herbal Remedies

"When seeking a licence for herbal medicines, many companies have had difficulty meeting

conventional requirements to prove efficacy. This was one factor that led to the introduction of the

Traditional Herbal Registration Scheme and many products are likely to follow that regulatory route." 

MHRA - Safeguarding public health report• 70 suspected adverse drug reports

relating to herbal remedies

• Handful of identified UK deaths

• Steady flow of cases entailing very serious illness e.g. kidney or liver failure

• BUT increasing study and scientific understanding of herbal medicines would be expected to improve safety profile

BAD MEDICINE - More cases of adverse side effects (The Singapore Straits Times, 11 October 2011)

Anaesthetic Concerns

“There are known knowns. These are things we know that we know. There are known

unknowns. That is to say, there are things that we know we don't know. But there are also

unknown unknowns. There are things we don't know we don't know.”

Anaesthetic concerns

• Unknown effects of herbal remedies

• Potential interactions with drugs

• Pre-operative

• Intra-operative

• Post-operative

• Effects on patient physiology

most common herbal medicines in the UK

• Echinacea

• Ginger

• St Johns Wort

• Garlic

• Saw palmetto

• Ephedra

• Ginseng

• Gingko

• Valerian

• Kava Kava

Echinacea (Echinacea Pururrea)

• Uses

• Common cold

• Wounds/Burns

• UTI

• URTI

• Possible side effects/interactions

• Hepatotoxicity

• Decrease efficacy of corticosteroids

St Johns Wort (Hypericum perforatum)

• Uses

• Depression

• Anxiety

• Possible side effects/interaction

• Induction of P450 3A4

• Serotonin syndrome

• Decrease efficacy of anti-HIV drugs

• Prolong effect of anaesthesia

• Organ rejection due to reduce immunosurpressants

Ephedra (Ephedra Sinica)

• Uses

• Antitussive

• Weight loss supplement

• Possible side effects/interactions

• Arrhythmias

• Enhanced sympathomimetic

• MAOI

• Death

Garlic (Allium sativum)• Uses

• Lipid lowering

• Blood pressure control

• Antiplatelet/Antithrombotic

• Antioxidants

• Possible side effects/interactions

• Potent inhibitor of thromboxane synthetase

• Increased bleeding time

• Epidural haematoma

ginseng (panax ginseng)• Uses

• Antioxidants

• Energy level enhancer

• Exam success

• Possible side effects/interactions

• Ginseng abuse syndrome

• sleepiness

• hypertonia

• oedema

• Interactions with antipsychotics

• Antiplatelet properties

• Increased bleeding

• Hypoglycaemia

• CVS instability

Canadian Anesthesiologists' Society

Can I take herbal and dietary supplements?

The use of herbal medicines is common. Herbal medicine is defined as a plant-derived product used for medicinal and health purposes; commonly used herbal supplements include echinacea, garlic, ginseng, ginkgo biloba, St John’s wort and valerian.

Herbal medicines can have a variety of effects on surgery and interact with anaesthetic drugs. Ginkgo, ginseng and garlic all impair blood clotting and promote excessive bleeding. Prolongation of action of anaesthesia drugs can occur with valerian and St John’s wort. Herbal dietary supplements should be stopped two weeks prior to surgery.

Fish oil supplements are also popular as a dietary supplement. They have potential in reducing cholesterol and hence may reduce the risk of heart attack and stroke. They also have anti-inflammatory properties and may be used to treat arthritis. The Therapeutic Goods Administration says that omega 3, which is found in fish oil, has no effect on bleeding and can be continued before surgery.

RCoA Patient Information Leaflet

• "It is important for you to bring a list of:

• "all the pills, medicines, herbal remedies or supplements you are taking, both prescribed and those that you have purchased over the counter"

• "If you are taking medicines, you should continue to take them as usual, unless your anaesthetist or surgeon has asked you not to. For example, if you take drugs to stop you getting blood clots (anticoagulants), aspirin, drugs for diabetes or herbal remedies, you will need specific instructions."

British association of Day Surgery (BADS)

british Association of Day Surgery (BADS)

“Current” UK practice• McKenzie and Simpson - Survey of AAGBI members (2005)

• 90% - never or seldom asked about herbal medicines

• 65% - thought there could be potential harm

• 75% - perioperative usage of herbal medicine is important

• “Unequivocally” poor knowledge

• Hogg and Foo - Survey of all anaesthetic dept (2010)

• 7.3% have perioperative herbal medicine policy

• 98.3% did not have specific section documenting herbal medicine use

• 15.7% routinely asked about herbal medicine use

• Highly variable advice given (not in accordance to existing guidelines)

Conclusion• The use of herbal remedies in patients

undergoing anaesthesia is under-reported.

• Side-effects and herb-drug interactions can be unknown.

• Elective surgery - all herbal medication should be stopped for between 2 and 3 weeks prior.

• Emergency surgery - carry on.

• Improved education and knowledge crucial.

References1. MHRA Public Health Risk with Herbal Medicines: An Overview (2010)

2. Hogg LA and Foo I. Management of patients taking herbal medcines in the perioperative period: a survey of practice and policies within Anaesthetic Departments in the UK. EJoA 2010; 27: 11-15.

3. American Society of Anesthesiolgist. What You Should Know About Your Patients’ Use of Herbal Medicines and Other Dietary Supplements (2010).

4. McKenzie AG and Simpson KR. Current management of patients taking herbal medicines: a survey of anaesthetic practice in the UK. EJoA 2005; 22: 597-602.

5. Cheng B, Hung CT, Chiu W. Herbal medicine and anaesthesia. HKMJ 2002; 8: 123-130.

6. Skinner CM and Rangasami J. Preoperative use of herbal medicines: a patient survey. BJA 2002; 89(5): 792-795.

7. Batra YK and Rajeev S. Effect of common herbal medicines on patients undergoing anaesthesia. IJoA 2007; 51(3): 184-192.

8. Hodges PJ and Kam PCA. The peri-operative implications of herbal medicines. Anaesthesia 2002; 57: 889-899.

9. Ang-Lee M, Moss J and Yuan CS. Herbal Medicines and Perioperative Care. JAMA 2001; 286: 208-216.