Trade names or approved names. Part III. Special cases. The digoxin affair.

The cardiac glycosides are potentially dangerous medicines and consistent preparations are necessary. However, presently used tablets of digoxin differ markedly in the fraction of the dose which is absorbed. Measurement of plasma digoxin levels by radioimmunoassay show that absorption from the Lanoxin brand has varied considerably in recent years due to changes in manufacturing technique. Other brands marketed in the U.K. form a wide range of bio-availability. Hazards to the patient are not entirely avoided by brand name prescribing and it is suggested that new pharmacopoeial standards are needed.