Drug interactions with herbal products and grapefruit juice: a conference report

Huang, Shiew Mei; Hall, Stephen D.; Watkins, Paul B.; Love, Lori A.; Serabjit‐Singh, Cosette J.; Betz, Joseph M.; Hoffman, Freddie Ann; Honig, Peter K.; Coates, Paul M.; Bull, J. P.; Chen, Shaw T.; Kearns, Gregory L.; Murray, Michael

doi:10.1016/j.clpt.2003.07.002

Cited by 86 publications

(51 citation statements)

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“…The interaction between grapefruit juice and drugs has been potentially ascribed to a number of constituents. QU is one the important flavonoid in grapefruit juice responsible for the interaction (Huang et al 2004). A few authors investigated the bioavailability of QU after several days or weeks of supplementation and stated that the elimination of QU metabolites is quite slow, with reported half-lives ranging from 11 to 28 hrs.…”

Section: Resultsmentioning

confidence: 99%

Comparative inhibitory potential of selected dietary bioactive polyphenols, phytosterols on CYP3A4 and CYP2D6 with fluorometric high-throughput screening

et al. 2014

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Cytochrome P450 (CYP450) inhibition by the bioactive molecules of dietary supplements or herbal products leading to greater potential for toxicity of co-administered drugs. The present study was aimed to compare the inhibitory potential of selected common dietary bioactive molecules (Gallic acid, Ellagic acid, β-Sitosterol, Stigmasterol, Quercetin and Rutin) on CYP3A4 and CYP2D6 to assess safety through its inhibitory potency and to predict interaction potential with co-administered drugs. CYP450-CO complex assay was carried out for all the selected dietary bioactive molecules in isolated rat microsomes. CYP450 concentration of the rat liver microsome was found to be 0.474 nmol/mg protein, quercetin in DMSO has shown maximum inhibition on CYP450 (51.02±1.24 %) but less when compared with positive control (79.02±1.61 %). In high throughput fluorometric assay, IC 50 value of quercetin (49.08±1.02-54.36± 0.85 μg/ml) and gallic acid (78.46±1.32-83.84±1.06 μg/ml) was lower than other bioactive compounds on CYP3A4 and CYP2D6 respectively but it was higher than positive controls (06.28±1.76-07.74±1.32 μg/ml). In comparison of in vitro inhibitory potential on CYP3A4 and CYP2D6, consumption of food or herbal or dietary supplements containing quercetin and gallic acid without any limitation should be carefully considered when narrow therapeutic drugs are administered together.

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Section: Resultsmentioning

confidence: 99%

Comparative inhibitory potential of selected dietary bioactive polyphenols, phytosterols on CYP3A4 and CYP2D6 with fluorometric high-throughput screening

et al. 2014

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“…This inverse association may be due to the 206 contribution of sugar-rich juices to total grapefruit intake. Furthermore, this detrimental 207 association may also be explained by be due to the findings that grapefruit components have 208 clinically significant interactions with drugs, which appear to be independent of their flavonoid 209 content 35 . However, this hypotheses were unable to be explored in this cohort.…”

Section: Discussion 172mentioning

confidence: 99%

Association of flavonoid-rich foods and flavonoids with risk of all-cause mortality

et al. 2017

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1Flavonoids are bioactive compounds found in foods such as tea, red wine, fruits, and vegetables. 2Higher intakes of specific flavonoids, and flavonoid rich foods, have been linked to reduced 3 mortality from specific vascular diseases and cancers. However, the importance of flavonoid-rich 4 foods, and flavonoids, in preventing all-cause mortality remains uncertain. As such, we 5 examined the association of intake of flavonoid-rich foods and flavonoids with subsequent 6 mortality among 93,145 young and middle-aged women in the Nurses' Health Study II. During 7 1,838,946 person-years of follow-up, 1,808 participants died. When compared to non-consumers, 8 frequent consumers of red wine, tea, peppers, blueberries, and strawberries were at reduced risk 9 of all-cause mortality (P<0.05), with the strongest associations observed for red wine and tea; 10 multivariable-adjusted hazard ratios (95%CI and cause-specific mortality. These findings support the rationale for making food-based dietary 21 recommendations. 22

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“…Minor constituents include various alkaloids, furanofuran lignans, and free amino acids (Houghton, 1999). Valerian is well recognized by its unpleasant odor that is attributed to isovaleric acid formation during processing and storage.The widespread use of valerian supplements suggests that use with conventional medications is inevitable, and the potential for drug interactions is undefined (Fugh-Berman and Ernst, 2001;Markowitz et al, 2003b;Huang et al, 2004). The present study was undertaken in healthy volunteers to determine whether a valerian supplement containing known quantities of valerenic acid and its derivatives could alter the activity of two major drug-metabolizing enzymes, cytochrome P450 2D6 (CYP2D6) and CYP3A4 in healthy volunteers.…”

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confidence: 99%

MULTIPLE NIGHT-TIME DOSES OF VALERIAN (Valeriana officinalis) HAD MINIMAL EFFECTS ON CYP3A4 ACTIVITY AND NO EFFECT ON CYP2D6 ACTIVITY IN HEALTHY VOLUNTEERS

Donovan

DeVane²,

Chavin³

et al. 2004

Drug Metab Dispos

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ABSTRACT:Valerian (Valeriana officinalis) is a popular dietary supplement. The objective of this study was to assess the influence of a valerian extract on the activity of the drug-metabolizing enzymes cytochrome P450 2D6 (CYP2D6) and 3A4. Probe drugs dextromethorphan (30 mg; CYP2D6 activity) and alprazolam (2 mg; CYP3A4 activity) were administered orally to healthy volunteers (n ‫؍‬ 12) at baseline and again after exposure to two 500-mg valerian tablets (1000 mg) nightly for 14 days. The valerian supplement contained a total valerenic acid content of 5.51 mg/tablet. Dextromethorphan to dextorphan metabolic ratios (DMRs) and alprazolam pharmacokinetics were determined at baseline and after valerian treatment. Valerian (Valeriana officinalis) extracts are marketed as dietary supplements in the United States and were among the top 10 bestselling herbal supplements in the United States in 2002 (Blumenthal, 2003). Although they are currently promoted as a sedative/hypnotic, clinical trials are presently inconclusive with regard to the efficacy for insomnia (Houghton, 1999;Stevinson and Ernst, 2000;Krystal and Ressler, 2001).Valerian supplements contain a complex mixture of chemical constituents (Shohet et al., 2001). The main constituents are valerenic acid and its derivatives contained in the volatile oil (Houghton, 1999). These main constituents are widely thought to contribute to the putative sedative effects, although clinical effects may be a result of synergistic activity from numerous constituents. The valepotriates have also been investigated for pharmacologic activity but are relatively unstable and are often not present in most commercial supplements (Bos et al., 2002). Minor constituents include various alkaloids, furanofuran lignans, and free amino acids (Houghton, 1999). Valerian is well recognized by its unpleasant odor that is attributed to isovaleric acid formation during processing and storage.The widespread use of valerian supplements suggests that use with conventional medications is inevitable, and the potential for drug interactions is undefined (Fugh-Berman and Ernst, 2001;Markowitz et al., 2003b;Huang et al., 2004). The present study was undertaken in healthy volunteers to determine whether a valerian supplement containing known quantities of valerenic acid and its derivatives could alter the activity of two major drug-metabolizing enzymes, cytochrome P450 2D6 (CYP2D6) and CYP3A4 in healthy volunteers. These two enzymes were chosen since, together, they contribute to the metabolism of a substantial number of both prescription and nonprescription medications (Wrighton and Thummel, 2000;Zanger and Eichelbaum, 2000;Burk and Wojnowski, 2004). To our knowledge, this is the first clinical study assessing whether a standardized valerian supplement may participate in drug interactions mediated by any of the P450 enzymes. Materials and MethodsSubjects. The study was approved by the Medical University of South Carolina's Office of Research Integrity, and subjects provided written informed consent before...

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Drug interactions with herbal products and grapefruit juice: a conference report

Cited by 86 publications

References 40 publications

Comparative inhibitory potential of selected dietary bioactive polyphenols, phytosterols on CYP3A4 and CYP2D6 with fluorometric high-throughput screening

Comparative inhibitory potential of selected dietary bioactive polyphenols, phytosterols on CYP3A4 and CYP2D6 with fluorometric high-throughput screening

Association of flavonoid-rich foods and flavonoids with risk of all-cause mortality

MULTIPLE NIGHT-TIME DOSES OF VALERIAN (Valeriana officinalis) HAD MINIMAL EFFECTS ON CYP3A4 ACTIVITY AND NO EFFECT ON CYP2D6 ACTIVITY IN HEALTHY VOLUNTEERS

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