Herbs have been in use for centuries to prevent and control disease. In recent history demand by the public for herbal supplements has created a multimillion-dollar industry. Herbal extracts are effective because they interact with specific chemical receptors within the body and are in a pharmacodynamic sense, drugs themselves.
A matter for public concern is that herbal supplements are currently independent of regulation by the Federal Drug Administration (FDA). The FDA considers herbal products to be dietary supplements, not drugs. The National Toxicology Program has recently started to examine the composition and standardization of commercial preparations to identify potential health hazards from contaminants or product over use. Many herbal preparations have significant pharmacological effects. The problem that arises for the dental professional is the effect these products have in concert with prescription medications as well as effects on the patient's general response to medication and dental treatment. Drug interactions with the large number of commercially available herbal products can be grouped by the mechanism of most common interactions. These major types of reactions are: (1) alteration of drug metabolizing enzyme activity, (2) interactions with the blood clotting process, and (3) alteration of the inflammatory and immune response.
The widespread use of herbal supplements makes it essential that healthcare providers become informed about this aspect of a patient's personal health practices.
Herbal medications for common ailments in the elderly. Drugs Aging. 1999 Dec;15(6):423-8.
Inflammation and Native American medicine: the roleof botanicals. Am J Clin Nutr. 2000 Aug;72(2):339-47. Review.
Echinacea root extracts for the prevention of upper respiratory tract infections: a double-blind, placebo-controlled randomized trial. Arch Fam Med. 1998 Nov-Dec;7(6):541-5.
“Echinacea: treatment or prevention?” Health News 1999;5:7.
Micronutrients as nutriceutical interventions in diabetes mellitus. J Am Coll Nutr. 1998 Feb;17(1):7-10. Review.
Over-the-counter psychotropics: a review of melatonin, St John's wort, valerian, and kava-kava. J Am Coll Health. 1998 May;46(6):271-6.
The Complete Guide to Herbal Medicine, Springhouse Corporation, Springhouse, PA, 2000.
Dietary supplement-drug interactions. J Am Med Womens Assoc. 1999 Fall;54(4):191-2,195. Review.
Herb-drug interactions. Lancet. 2000 Jan 8;355(9198):134-8. Review.
A review of 12 commonly used medicinal herbs. Arch Fam Med. 1998 Nov-Dec;7(6):523-36. Review.
Inhibition of monoamine oxidase by hypericin. Planta Med. 1984 Jun;50(3):272-4. No abstract available.
Herbal remedies in psychiatric practice. Arch Gen Psychiatry. 1998 Nov;55(11):1033-44. Review.
The relevance of herbal treatments for psychiatric practice. Aust N Z J Psychiatry. 1999 Aug;33(4):482-9; discussion 490-3. Review.
Skin photosensitization with topical hypericin in hairless mice. J Photochem Photobiol B. 1999 Nov-Dec;53(1-3):110-4.
Phase I studies of hypericin, the active compound in St. John's Wort, as an antiretroviral agent in HIV-infected adults. AIDS Clinical Trials Group Protocols 150 and 258. Ann Intern Med. 1999 Mar 16;130(6):510-4.
Bromohypericins are potent photoactive antiviral agents. Photochem Photobiol. 1999 Nov;70(5):820-2.
Hypericin: a potential antiglioma therapy. Neurosurgery. 1994 Oct;35(4):705-9; discussion 709-10.
Photodynamic effects of hypericin on lipid peroxidation and antioxidant status in melanoma cells. Photochem Photobiol. 1996 Aug;64(2):375-81.
Hypericin: a new laser phototargeting agent for human cancer cells. Laryngoscope. 1996 Apr;106(4):479-83.
The effect of hypericin as a sensitizer of biological systems against visual and ionizing radiation. Radiobiol Radiother 1965;6(4):477-83.
Inhibition of MAO by fractions and constituents of hypericum extract. J Geriatr Psychiatry Neurol. 1994 Oct;7 Suppl 1:S57-9.
Neuropharmacology of St. John's Wort (Hypericum). Ann Pharmacother. 1998 Nov;32(11):1201-8. Review.
Inhibition of MAO and COMT by hypericum extracts and hypericin. J Geriatr Psychiatry Neurol. 1994 Oct;7 Suppl 1:S54-6.
SSRI's and St. John's wort: Possible toxicity? Am Fam Phys 1998;57:28-32.
St. John's wort tied to serotonin syndrome. Clin Psychiatry News 1998;26:28-29.
St. John's wort and antidepressant drug interactions in the elderly. J Geriatr Psychiatry Neurol. 1999 Spring;12(1):7-10.
The serotonin syndrome. Am J Psychiatry. 1991 Jun;148(6):705-13. Review.
St John's Wort: effect on CYP3A4 activity. Clin Pharmacol Ther. 2000 May;67(5):451-7.
Inhibition of human cytochrome P450 enzymes by constituents of St. John's Wort, an herbal preparation used in the treatment of depression. J Pharmacol Exp Ther. 2000 Jul;294(1):88-95.
Induction of microsomal cytochrome P-450 enzymes: the first Bernard B. Brodie lecture at Pennsylvania State University. Life Sci. 1986 Dec 29;39(26):2493-518. Review. No abstract available.
Acute heart transplant rejection due to Saint John's wort. Lancet. 2000 Feb 12;355(9203):548-9.
Indinavir concentrations and St John's wort. Lancet. 2000 Feb 12;355(9203):547-8.
[Drug interactions of Hypericum perforatum (St. John's wort) are potentially hazardous]. Ned Tijdschr Geneeskd. 2000 Apr 22;144(17):811-2. Review. Dutch.
Mdr1 limits CYP3A metabolism in vivo. Mol Pharmacol. 2000 Oct;58(4):863-9.
An in vitro model for predicting in vivo inhibition of cytochrome P450 3A4 by metabolic intermediate complex formation. Drug Metab Dispos. 2000 Sep;28(9):1031-7.
An in vitro evaluation of human cytochrome P450 3A4 inhibition by selected commercial herbal extracts and tinctures. Phytomedicine. 2000 Jul;7(4):273-82.
Herbal medicine for the treatment of cardiovascular disease: clinical considerations. Arch Intern Med. 1998 Nov 9;158(20):2225-34. Review.
Garlic powder in the treatment of moderate hyperlipidaemia: a controlled trial and meta-analysis. J R Coll Physicians Lond. 1996 Jul-Aug;30(4):329-34.
Garlic powder and plasma lipids and lipoproteins: a multicenter, randomized, placebo-controlled trial. Arch Intern Med. 1998 Jun 8;158(11):1189-94.
A meta-analysis of the effect of garlic on blood pressure. J Hypertens. 1994 Apr;12(4):463-8.
Effect of garlic on human platelet aggregation in vitro. Atherosclerosis. 1978 Aug;30(4):355-60.
Dietary supplementation with aged garlic extract inhibits ADP-induced platelet aggregation in humans. J Nutr. 2000 Nov;130(11):2662-5.
Vertigo-reducing effect of ginger root. A controlled clinical study. ORL J Otorhinolaryngol Relat Spec. 1986;48(5):282-6.
Ginger: history and use. Adv Ther. 1998 Jan-Feb;15(1):25-44. Review.
Ginger: inhibition of thromboxane synthetase and stimulation of prostacyclin: relevance for medicine and psychiatry. Med Hypotheses. 1986 Jul;20(3):271-8. Review.
Ginger as an antiemetic: possible side effects due to its thromboxane synthetase activity. Anaesthesia. 1991 Aug;46(8):705-6. No abstract available.
NCDEU update. Natural product formulations available in europe for psychotropic indications. Psychopharmacol Bull. 1995;31(4):745-51. Review.
A placebo-controlled, double-blind, randomized trial of an extract of Ginkgo biloba for dementia. North American EGb Study Group. JAMA. 1997 Oct 22-29;278(16):1327-32.
Effect of a ginkgolide mixture (BN 52063) in antagonising skin and platelet responses to platelet activating factor in man. Lancet. 1987 Jan 31;1(8527):248-51.
Spontaneous bilateral subdural hematomas associated with chronic Ginkgo biloba ingestion. Neurology. 1996 Jun;46(6):1775-6. No abstract available.
Evaluation of commercial ginseng products. J Pharm Sci. 1978 Oct;67(10):1487-9.
Consumer Reports 1995;698-705.
Ginseng therapy in non-insulin-dependent diabetic patients. Diabetes Care. 1995 Oct;18(10):1373-5.
Probable interaction between warfarin and ginseng. Am J Health Syst Pharm. 1997 Mar 15;54(6):692-3. No abstract available.
Herbal medicinals: selected clinical considerations focusing on known or potential drugherb interactions. Arch Intern Med. 1998 Nov 9;158(20):2200-11. Review.
Herbal remedies: adverse effects and drug interactions. Am Fam Phys. 1999 Mar 1;59(5):1239-45. Review.
Ginseng face cream and unexplained vaginal bleeding. Am J Obstet Gynecol. 1988 Nov;159(5):1121-2.
Possible influences of ginseng on the pharmacokinetics and pharmacodynamics of warfarin in rats. J Phar Pharmacol. 1999 Feb;51(2):175-80.
Efficacy and mode of action of an immunomodulator herbal preparation containing Echinacea, wild indigo, and white cedar. Adv Ther. 1999 Jan-Feb;16(1):51-70. Review.
The American coneflower: a prophylactic role involving nonspecific immunity. J Altern Complement Med. 1999 Oct;5(5):437-46.
Increased production of antigen-specific immunoglobulins G and M following in vivo treatment with the medicinal plants Echinacea angustifolia and Hydrastis canadensis. Immunol Lett. 1999 Jun 1;68(2-3):391-5.
In vitro effects of echinacea and ginseng on natural killer and antibody-dependent cell cytotoxicity in healthy subjects and chronic fatigue syndrome or acquired immunodeficiency syndrome patients. Immunopharmacology. 1997 Jan;35(3):229-35.
Echinaforce and other Echinacea fresh plant preparations in the treatment of the common cold. A randomized, placebo controlled, double-blind clinical trial. Phytomedicine. 1999 Mar;6(1):1-6.
Results of five randomized studies on the immunomodulatory activity of preparations of Echinacea. J Altern Complement Med. 1995 Summer;1(2):145-60.
, Eds. (1998). German Commision E Monographs: Therapeutic monographs on medicinal plants. Austin, TX, American Botanical Council.
Phenytoin suppositories and echinacea. S D J Med. 1997 Sep;50(9):335. No abstract available.
Scope and limitation of the application of the (methoxydimethyl)methyl group in the synthesis of 2'-O-, 6'-O- and 2',6'-di-O-(alpha-L-arabinofuranosyl)-beta-D-galactopyranosyl- (1-->6)-D-galactoses. Carbohydr Res. 1999 May 31;318(1-4):98-109.
In vitro inhibition of arachidonate metabolism by some alkamides and prenylated phenols. Planta Med 1989;55: 566-567.
In vitro inhibition of cyclooxygenase and 5-lipoxygenase by alkamides from Echinacea and Achillea species. Planta Med. 1994 Feb;60(1):37-40.
Benzophenanthridine alkaloids of Chelidonium majus; I. Inhibition of 5- and 12-lipoxygenase by a non-redox mechanism. Planta Med. 1996 Oct;62(5):397-401.
Evening primrose oil and borage oil in rheumatologic conditions. Am J Clin Nutr. 2000 Jan;71(1 Suppl):352S-6S. Review.
Essential fatty acid metabolism in diseases of connective tissue with special reference to scleroderma and to Sjogren's syndrome. Med Hypotheses. 1984 Jul;14(3):233-47.
Metabolism of polyunsaturated fatty acids by skin epidermal enzymes: generation of antiinflammatory and antiproliferative metabolites. Am J Clin Nutr. 2000 Jan;71(1 Suppl):361S-6S. Review.
Primary Sjogren's syndrome treated with Efamol/Efavit. A double-blind cross-over investigation. Rheumatol Int. 1984;4(4):165-7.
US sees the green in herbal supplements. Chem Market Rep 1998;(254): FR 3-4.