DIGOXIN AND HERBAL MEDICINES OR DIETARY SUPPLEMENTS - CHINESE HERBAL MEDICINES
Chinese medicines that contain bufalin, such as Chan Su, Lu-Shen-Wan and Kyushin, can interfere with some immunoassay methods of digoxin, particularly the fluores- cence polarisation immunoassay. Similarly, a study found that a fluorescent polarization immunoassay method (Abbott Laboratories) for digoxin gave falsely high readings in the presence of danshen, whereas a microparticle enzyme immunoassay (Abbott Laboratories) gave falsely low readings.
It has been suggested that the false readings caused by bufalin could be eliminated by monitoring the free (i.e. unbound) digoxin concentrations or by using a chemiluminescent assay. Similarly, to reduce the interference from danshen, measure free digoxin levels or choose assay systems that are unaffected by the presence of danshen (said to be the Roche and Beckman systems or an enzyme linked chemiluminescent immunisorbent digoxin assay by Bayer HealthCare).
It has been suggested that the false readings caused by bufalin could be eliminated by monitoring the free (i.e. unbound) digoxin concentrations or by using a chemiluminescent assay. Similarly, to reduce the interference from danshen, measure free digoxin levels or choose assay systems that are unaffected by the presence of danshen (said to be the Roche and Beckman systems or an enzyme linked chemiluminescent immunisorbent digoxin assay by Bayer HealthCare).