1. JEANNA M. HICKS MSN, RN OCTOBER 2010 Herbal Remedies and Drug Interactions

2. A Bit Of History The practice of herbal medicine is as old as mankind itself Every human culture on every continent has practices it in one form or another

3. A Bit Of History About 25% of today’s drugs contain ingredients isolated from plants Salicylic acid (Aspirin) is derived from while willow bark Vincristine (A form of chemotherapy) Morphine is derived from the opium poppy

4. A Bit Of History In the US, botanical products are now a $1.5 billion per year industry It is estimated that 60 to 70% of the American population is taking botanical products However less than one third of these inform their medical practitioners of their use

5. A Bit Of History Because herbs are sold as food supplements, companies are not required to prove their efficacy. Side effects or interactions are also not required to be determined or disclosed. No government agency reviews these products for safety, dosage, or quality.

6. A Bit Of History In 1994, the Dietary Supplement and Health Education Act (DSHEA) was enacted. Created the new category of dietary supplements. This exempts herbal products from the rigorous safety and efficacy testing required by the FDA.

7. A Bit Of History Manufacturers and distributors may now market any herbal or botanical product without prior approval by the FDA as long as the label does not claim effectiveness for the treatment or prevention of a specific disease. Must have a disclaimer stating that the FDA has not evaluated the product.

8. A Bit Of History The manufacturer alone is responsible for quality control. The burden of proof regarding safety issues lies with the FDA.

9. A Bit Of History Many products are perfectly safe. However, 2621 adverse events associated with dietary supplements, including 101 deaths, were reported to the FDA over a 5-year period.

10. Common Pitfalls Multiple ingredients are present in the same bottle. Products are sometimes mislabeled or misidentified Potency can vary depending on the climate and soil in which the herbs are grown.

11. Common Pitfalls When a drug is prescribed, the dosage and quality of the product is more or less assured. This is not the case with herbs since there is no real quality control.

12. Drug-Herb Interactions Pharmacokinetic interactions : Having to do with absorption, distribution, and metabolism. Pharmacodynamic interactions: Additive activity meaning that certain herbs increase the actions of certain medications.

13. Pharmacokinetic Interactions: Absorption Some herbs have hydrocollated carbohydrate components such as gums and mucliage. These are soluble in water but poorly absorbable. Examples are psyllium, rhubarb, flaxseed, and marshmallow.

14. Pharmacokinetic Interactions: Absorption Bind to other drugs, particularly when consumed in their whole or powdered forms. Psyllium inhibits the absorption of lithium. Rhubarb and aloe can cause diarrhea which reduces the actions of drugs that have a narrow therapeutic index (digoxin, warfarin)

15. Pharmacokinetic Interactions: Absorption In order to prevent an herb from binding with drugs, the drug should be taken one hour before or two hours after these herbal products.

16. Pharmacokinetic Interactions: Distribution Meadowsweet and black willow contain pain reducing salicylates. These may displace highly protein bound drugs such as warfarin and carbamezepine (Tegretol). This increases the adverse effects of these drugs. Do not take these products concurrently

17. Pharmacokinetic Interactions: Metabolism When taken as an herb, licorice decreases the metabolism of corticosteroids. This leads to adverse and toxic effects from the buildup of corticosteroids. St. John’s wort increases the metabolism of drugs in the liver.

18. Pharmacodynamic Interactions Additive activity The hypnotic activity of benezodiazepines is increased by valerian. Anticoagulant action of warfarin is enhanced by ginko

19. Ginkgo (Ginkgo biloba) Used by elderly persons because of its ability to improve cognitive function in persons with Alzheimer’s and dementia. Reports of bleeding associated with ginkgo use have been reported.

20. Ginkgo (Ginkgo biloba) Patients ranged from 33 to 78 years old One person was taking no other drugs concurrently. Others were taking aspirin, warfarin, acetaminophen, or an ergotamine- caffeine preparation concurrently. Episodes were both minor and major One death from cerebral hemorrhage.

21. Gingko (Gingko biloba) Caution patients who are also taking Vitamin E, warfarin, aspirin, and low molecular weight heparin about the potential interactions with ginkgo. If taking ginkgo, counsel them to report any unusual bleeding, bruising, or an new onset of dizziness, headache, or blurred vision to their healthcare provider.

22. Flaxseed (Linum usitatissimum) Flax is one of the oldest cultivated plants in the world. A bulk-producing, stool softening agent that lowers levels of cholesterol, triglycerides, and low-density lipoproteins. Binds to bile acids in the intestinal tract and interferes with the reabsorption of fats.

23. Flaxseed (Linum usitatissimum) When soaked, flaxseeds can bind with other drugs, especially cardiac glycosides rendering them unabsorable. Take flaxseed wither two hours before or two hours after taking other meds. Concurrent use with laxatives and stool softeners should be avoided because of possible potentiation of the laxative effect.

24. Feverfew (Tanacetum parthenium) Most commonly used to reduce the number and severity of migraine headaches. Inhibits platelet activity, so it should not be taken concurrently with warfarin or other drugs that affect clotting. A member of the daisy family, it is contraindicated in patients with allergy to ragweed.

25. Ginger (Zingiber officinale) Used and tested as an antinausea and antispasmodic agent with good results. Potent inhibitor of thromboxane synthetase. Prolongs bleeding times. If taking warfarin or other drugs that affect platelet activity, avoid ginger in tablet form.

26. Kava Kava (Piper methysticum) Relieves anxiety, nervousness, and tension. Does not affect alertness. Acts as a dopamine antagonist. May increase tremor and decrease response to anti-Parkinsonian meds.

27. Kava Kava (Piper methysticum) Potentiates alcohol Potentiates tranquilizers Potentiates antidepressants Do not take any of these concurrently with Kava

28. St. John’s Wort (Hypericum perforatum) One of the most popular herbs in the US for the treatment of depression. Current research shows that it acts as a selective serotonin reuptake inhibitor (SSRI) Because of this, concurrent use with SSRIs is prohibited.

29. St. John’s Wort (Hypericum perforatum) Patients should wait 2 weeks after taking an SSRI before beginning St. John’s wort. Newest research suggests that it may act in the cytochrome P-450 of the liver. Interferes with metabolism of certain protease inhibitors used in the treatment of HIV.

30. St. John’s Wort ( Hypericum perfortum) Associated with photosensitivity. Do not take concurrently with other photosensitizing herbs or drugs. If taking St. John’s wort, limit sun exposure.

31. Implications For Anesthesia and Moderate Sedation Morbidity secondary to botanical product use may be more prevalent in the perioperative period because of multiple drug use and increased physiological susceptibility to adverse effects.

32. Implications For Anesthesia and Moderate Sedation The problem is complicated by patients’ reluctance to report their use of herbal medicines or dietary supplements. 70% of presurgical patients failed to disclose their use of such products during routine preoperative assessment.

33. Reasons For Not Reporting Use of Herbal Medications A belief that because such products are “natural,” they must be safe. Fear of how healthcare providers would respond to self-medication. Fear that their physician may be prejudiced against use of botanicals.

34. Adverse Effects Cardiac Instability Electrolyte disturbances Prolonged bleeding Excessive sedation

35. Cardiovascular Effects of Anesthesia Decreased myocardial contractility Decreased vascular smooth muscle tone Arrhythmias Decreased cardiac output Avoid botanicals with blood pressure altering or arrhythmogenic potential

36. Ephedra Alkaloids Also known as ma-huang Common ingredient in many herbal weight loss and energy boosters Often packaged in combination with guarana (caffeine) Use has been linked to hypertension, palpitations, tachycardia, seizures, stroke, heart attack, and sudden death.

37. Ephedra Alkaloids Ephedra has been identified as the herbal product with the greatest potential for harm in perioperative patients.

38. Prolonged Bleeding Feverfew Ginger Gingko Horse chestnut Pau d’arco Danshen Garlic Saw palmetto

39. Prolonged Bleeding Gingko has been linked to a spontaneous hyphema in a 70 year old man who took 40mg of Gingko extract twice a day along with 325 mg of Aspirin daily for one week. Also bilateral subdural hematomas in a 33 year old woman who took 60 mg of Gingko twice a day for two years.

40. Prolonged Bleeding Certain herbs increase INR Danshen Dong quai (Used primarily in China but gaining popularity in the US) Paparin

41. Prolonged Bleeding Certain herbs contain coumarin or coumarin derviatives Angelica root Anise Licorice Red clover Rue

42. Prolonged Bleeding Antiplatelet activity Tumeric Clove Onion Bromelain Willow bark Meadowsweet

43. Excessive Sedation Any herb with inherent sedative effects can potentially delay emergence from anesthesia. Sedative herbs include kava, hawthorne and St. John’s wort. There has been a report of an interaction between kava and alprazolam that resulted in a semicomatose state.

44. Excessive Sedation St. John’s wort is believed to have some of the same effects as MAOIs. MAOIs may result in hypotension and exaggeration of the respiratory and CNS depressant effects of the narcotics. Because of this St. John’s wort should be discontinued before a procedure where narcotic analgesia is anticipated

45. Excessive Sedation Valerian is a popular herb used as a sleep aid and anxyiolytic. An extract of valerian containing valeric acid has been shown to prolong barbituate induced sleeping time. Considered safe as a food additive but has the potential for prolonging sedation.

46. Echinacea Used to boost the immune system and guard against colds and flu. May cause hepatotoxicity especially when used with certain hepatotoxic drugs. Examples are methotrexate or anabolic steroids.

47. Echinacea Many medications used during anesthesia are metabolized in the liver. Hepatic dysfunction may be a risk in certain patients who use echinacea.

48. Ginseng Used to support overall health and boost the immune system. May also be used to increase stamina, promote a sense of well-being, control blood pressure, and lower blood glucose levels. Excessive use may cause hypertension, and CNS stimulation.

49. Ginseng May also reduce opioid’s analgesic effects. May cause hypoglycemia in patients taking insulin or oral diabetic agents. Monitor blood glucose levels closely in patients who have been taking ginseng. May increase warfarin’s anticlotting effect.

50. Guarana Marketed as a CNS stimulant. Contains a high concentration of caffeine and is found in many antifatigue products. If taken in combination with SNS can cause cardiac arrest. May also decrease cerebral blood flow

51. Nursing Implications Patients are reluctant to reveal their use of dietary supplements to their health care providers. Caregivers should be aware of the many potential interactions with patients undergoing anesthesia or moderate sedation.

52. Nursing Implications Make sure to get an accurate, nonjudgmental, and thorough history of all medication use. Encourage the patient to discuss their use of herbals. This screening should be a routine part of all preanesthetia screening.

53. Nursing Implications This screening should take place far enough in advance to allow for discontinuation of potentially dangerous interactions. Patients should discontinue their herbal preparations at least two to three weeks before surgery.

54. Nursing Impications Safe, effective care requires awareness of all your patients’ use of herbal supplements and knowledge of their potential interactions with anesthestics and drugs used during moderate sedation. Include all medications when reviewing your patients’ meds before their procedure.