Article

Interactions Between Herbal Medicines and Prescribed Drugs. An Updated Systematic Review

Department of Experimental Pharmacology, University of Naples Federico II, via D Montesano 49, Naples 80131, Italy.
Drugs (Impact Factor: 4.34). 02/2009; 69(13):1777-98. DOI: 10.2165/11317010-000000000-00000
Source: PubMed

ABSTRACT

The concomitant use of herbal medicines and pharmacotherapy is wide spread. We have reviewed the literature to determine the possible interactions between seven popular herbal medicines (ginkgo, St John’s wort, ginseng, garlic, echinacea, saw palmetto and kava) and conventional drugs. Literature searches were performed using MEDLINE, Cochrane Library and EMBASE and we identified 128 case reports or case series, and 80 clinical trials.

Clinical trials indicate that St John’s wort (Hypericum perforatum), via cytochrome P450 (CYP) and/or P-glycoprotein induction, reduces the plasma concentrations (and/or increases the clearance) of alprazolam, amitriptyline, atorvastatin, chlorzoxazone, ciclosporin, debrisoquine, digoxin, erythromycin, fexofenadine, gliclazide, imatinib, indinavir, irinotecan, ivabradine, mephenytoin, methadone, midazolam, nifedipine, omeprazole, oral contraceptives, quazepam, simvastatin, tacrolimus, talinolol, verapamil, voriconazole and warfarin. Case reports or case series suggest interactions of St John’s wort with adrenergic vasopressors, anaesthetics, bupropion, buspirone, ciclosporin, eletriptan, loperamide, nefazodone, nevirapine, oral contraceptives, paroxetine, phenprocoumon, prednisone, sertraline, tacrolimus, theophylline, tibolone, tryptophan, venlafaxine and warfarin. Ginkgo (Ginkgo biloba) decreases the plasma concentrations of omeprazole, ritonavir and tolbutamide. Clinical cases indicate interactions of ginkgo with antiepileptics, aspirin (acetylsalicylic acid), diuretics, ibuprofen, risperidone, rofecoxib, trazodone and warfarin. Ginseng (Panax ginseng) may interact with phenelzine and warfarin. Kava (Piper methysticum) increases the clearance of chlorzoxazone (a CYP2E1 substrate) and may interact with alprazolam, levodopa and paroxetine. Garlic (Allium sativum) interacts with chlorpropamide, fluindione, ritonavir and warfarin; it also reduces plasma concentrations of chlorzoxazone (a CYP2E1 probe). Echinacea might affect the clearance of caffeine (a CYP1A2 probe) and midazolam (a CYP3A4 probe). No interactions have been reported for saw palmetto (Serenoa repens.)

Numerous interactions between herbal medicines and conventional drugs have been documented. While the significance of many interactions is uncertain, several interactions, particularly those with St John’s wort, may have serious clinical consequences.

Full-text preview

Available from: aspergillus.org.uk
  • Source
    • "The probe drugs were selected in accordance with existing studies, such as a Pittsburgh cocktail study[11], a Cooperstown cocktail study[12]and an Inje cocktail study[13]. Many natural materials can affect efflux proteins such as P-gp[14], even though conventional cocktail combinations do not include a drug that probes for this protein. To assess CYP enzyme activity, the present approach incorporated the cocktail combination of the Inje study, a previous drug interaction study that used a cocktail technique to evaluate general drug interactions by calculating metabolic ratios for a probe and its metabolite in plasma at certain time points. "
    [Show abstract] [Hide abstract]
    ABSTRACT: We evaluated the drug interaction profile of Red Ginseng (RG) with respect to the activities of major cytochrome P450 (CYP) enzymes and the drug transporter P-glycoprotein (P-gp) in healthy Korean volunteers.
    Full-text · Article · Jan 2016 · Journal of ginseng research
  • Source
    • "Many patients have misconceptions about dietary supplements, such as that " natural " is synonymous for safe, that supplements are safer than prescribed drugs, that megadoses are safe, and that the products and advertisements are preapproved by the FDA. Dietary supplements may interact with prescription drugs or with other dietary supplements (Izzo and Ernst 2009). Most interactions with dietary supplements reported in the literature involve prescription drugs that affect the central nervous system or cardiovascular system (Tsai et al. 2012). "

    Full-text · Article · Sep 2015
  • Source
    • "They serve as therapeutic agents as well as important raw materials for the manufacture of traditional and modern medicine. In present decades, there is increasing interest to unlock the secrets of ancient herbal remedies (Izzo and Ernst, 2009).The natural products of plant origin are a rich source of cancer chemotherapy drugs, and exhibited low or almost no toxicity to normal tissues; hence, more attention is being paid to searching for new antitumor agents from natural products (Dai et al., 2011). More than 60% of the anticancer agents used today are derived directly or indirectly from natural sources Cragget al. (1997). "
    Dataset: 17714530514

    Full-text · Dataset · Aug 2015
Show more