Digoxin interactions hawthorn

Drug interactions with hawthorn are theoretically possible with cardioactive medications, but have not been documented (2). In addition, the flavonoid constituents have been shown to have inhibitory and inducible effects on the cytochrome P-450 enzyme system, making other drug interactions possible (20). However, an in vivo study of a potential pharmacokinetic interaction of digoxin and hawthorn demonstrated that concurrent administration had no effect on digoxin pharmacokinetics, suggesting that the two could be safely administered together from a pharmacokinetic point of view (21). However, one must be mindful of additive effects and a potential pharmacodynamic interaction. 

Tankanow R, Tamer HR, Streetman DS, et al. Interaction study between digoxin and a preparation of hawthorn Crataegus oxyacantha). J Clin Pharmacol 2003 43 637-642. 

Some experience suggests that the dose of cardiac drugs may be reduced when hawthorn flower and leaf are taken concomitantly (Ammon and Haendel 1981 Bauer and Holscher 1992 Blesken 1992 van Hellemont and Delfosse 1988). No interaction with digoxin was observed in a human study (Tankanow et al. 2003). 

Dasgupta A, Kidd L, Poindexter BJ, Bick RJ. Interference of hawthorn on serum digoxin measurements by immunoassays and pharmacodynamic interaction with digoxin. Arch Pathol Lab Med 2010 134(8) 1188-92. 

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