Ginkgo biloba pharmacokinetics

Fourtillan JB, Brisson AM, Girault J, Ingrand I, Decourt JP, Drieu K, Jouenne P, Biber A. (1995). [Pharmacokinetic properties of bilobalide and ginkgolides A and B in healthy subjects after intravenous and oral administration of Ginkgo biloba extract (EGb 761)]. Therapie. 50(2) 137-44. Frewer U. (1990). The effect of betel nut on human performance. PNG MedJ. 33(2) 143-5. 

Wojcicki J, Gawroska-Szkiarz B, Bieganowski W, Patalan M, Smulski HK, Samochowiec L, Zakrzewski J. (1995). Comparative pharmacokinetics and bioavailability of flavonoid glycosides of Ginkgo biloba after a single oral administration of three formulations to healthy volunteers. Materia Med Polona. 27(4) 141-46. 

Yasui-Furukori N, Furukori H, Kaneda A, Kaneko S, Tateishi T. The effects of Ginkgo biloba extracts on the pharmacokinetics and pharmacodynamics of donepezil. J Clin Pharmacol 2004 44 538-542. 

Fourtillan JB, Brisson AM, Girault J, et al. Pharmacokinetic properties of bilobalide and ginkgolides A and B in healthy subjects after intravenous and oral administration of Ginkgo biloba extract (EGb 761). Therapie 1995 50 137-144. 

Drago F, Floriddia ML, Cro M, Giuffrida S. Pharmacokinetics and bioavailability of a Ginkgo biloba extract. J Ocul Pharmacol Ther 2002 18 197-202. 

Yin OQP, Tomlinson B, Waye MMY, Chow AHL, Chow MSS. Pharmacokinetics and herb-drug interactions experience with Ginkgo biloba and omeprazole. Pharmacogenetics 2004 14 841-850. 

Unger M (2013) Pharmacokinetic drug interactions involving Ginkgo biloba. Drug Metab Rev 45 353-385... 

The incidence of phenytoin toxicity may be increased in the eideriy, or in those patients with hepatic or renal impairment, because of alterations in its pharmacokinetics. Plasma level determinations may be indicated in these cases. Although a role for P-glycoprotein transporter alleles in the development of phenytoin toxicity remains controversial, phenytoin is a robust substrate for the non-ABC efflux transporter RLIP76. Because RLIP76 has been found to be overexpressed in excised human epileptic foci, its action may account for treatment failures conversely, inhibition of transport may cause toxicity (34). There is a 2 to 3% increase in the risk of fetal epilepsy syndrome if the mother is taking phenytoin. Phenytoin is contraindicated in cardiac patients with bradyarrhythmias. Induction of CYP2C19 by ginkgo biloba may increase phenytoin clearance and precipitate serious seizures (35). 

A placebo-controlled study in 11 healthy subjects who were given Ginkgo biloba leaf (Ginkgold) 120 mg twice daily for three doses, followed by a single 100-mg dose of flurbiprofen, found that the pharmacokinetics of flurbiprofen were unchanged. ... 

The pharmacokinetic study involving diclofenac was designed to identify whether Ginkgo biloba exerted an inhibitory effect on cytochrome P450 isoenzyme CYP2C9, which is involved in the metabolism of diclofenac. Although an indication that such an effect may occur was noted in studies in vitro using S-warfarin, the in vivo study did not confirm that this interaction would be seen clinically. ... 

In a pharmacokinetic study 14 elderly patients with Alzheimer s disease were given donepezil 5 mg daily for at least 20 weeks, after whieh Ginkgo biloba extract 90 mg daily was also given for a further 30 days. Coneur-rent use did not affect the pharmacokinetics or cholinesterase aetivity of donepezil, and cognitive function appeared to be unehanged. Therefore, over the course of 30 days, coneurrent use appears neither benefieial nor detrimental. 

Ginkgo biloba does not significantly affect the pharmacokinetics of alprazolam. 

A study in 8 healthy subjects found that ginkgo biloba leaf extract 80 mg three times daily had no significant effects on the pharmacokinetics of a single 500-microgram dose of digoxin. ... 

Kim, B.H., K.P. Kim, K.S. Lim, et al. 2010. Influence of Ginkgo biloba extract on the pharmacodynamic effects and pharmacokinetic properties of ticlopidine An open-label, randomized, two-period, two-treatment, two-sequence, single-dose crossover study in healthy Korean male volimteers. Clin. Ther. 32(2) 380-390. 

Lei, H.P., G. Wang, L.S. Wang, et al. 2009b. Lack of effect of Ginkgo biloba on voriconazole pharmacokinetics in Chinese volunteers identified as CYP2C19 poor and extensive metaboUzers. Ann. Pharmacother. 43(4) 726-731. 

Robertson, S.M., R.T. Davey, J. VoeU, et al. 2008. Effect of Ginkgo biloba extract on lopinavir, midazolam and fexofenadine pharmacokinetics in healthy subjects. Curr. Med. Res. Opin. 24(2) 591-599. 

Uchida, S., H. Yamada, X.D. Li, et al. 2006. Effects of Ginkgo biloba extract on pharmacokinetics and pharmacodynamics of tolbutamide and midazolam in healthy volunteers. J. Clin. Pharmacol. 46(11) 1290-1298. 

Yoshioka, M., N. Ohnishi, T. Koishi, et al. 2004. Studies on interactions between functional foods or dietary supplements and medicines. IV. Effects of Ginkgo biloba leaf extract on the pharmacokinetics and pharmacodynamics of nifedipine in healthy volunteers. Biol. Pharm. Bull. 27(12) 2006-2009. 

Zuo, X.C., B.K. Zhang, S.J. Jia, et al. 2010. Effects of Ginkgo biloba extracts on diazepam metabolism A pharmacokinetic study in healthy Chinese male subjects. Eur. J. Clin. Pharmacol. 66(5) 503-509. 

Tang DQ, Yin XX, Zhang ZJ, Gao YY, Wei YQ, Chen YG, Han L (2009) Gradient HPLC-DAD for the simultaneous determination of five flavonoids in plasma after intravenously administrated Ginkgo biloba extract and its application in the study of pharmacokinetics in rats. J Liq Chromatogr R T 32 2065-2079... 

Hu J, Zhao Y, Ma C, Wang W, Xing D, Du L (2010) Acid hydrolytic method for determination of Ginkgo biloba total flavonoids in rat plasma by HPLC for pharmacokinetic studies. Tsinghua Sci Technol 15 452-459... 

Blonk M, Colbers A, Poirters A, Schouwenberg B, Burger D. Effect of ginkgo biloba on the pharmacokinetics of raltegravir in healthy... 

An interaction between G. biloba administered as 80 mg leaf extract twice a day and low-dose trazodone (20 mg twice daily) was suspected in a patient with Alzheimer s disease, who took the two products together. It is postulated that a pharmacodynamic (increased gamma-aminobutyric acid-ergic activity) and pharmacokinetic mechanisms [increased metabolism of trazodone to w-chlorophenylpiperazine (w -CPP), which acts on the benzodiazepine-binding sites and releases gamma-aminobutyric acid] contribute to the observed effect (32). Table 2 provides a list of reported pharmacodynamic and pharmacokinetic interactions involving ginkgo. 

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