Low Drug Levels are As Bad As High Levels

This is not just a matter of reduced potency, but rather precision. Obtaining too high a plasma concentration with a change in formulation places the patient in grave danger. This is most clearly manifest with antiarrhythmic drugs and anticoagulants wherein excess concentrations can lead to ventricular proarrhythmia/heart block and serious bleeding respectively. There is no hope of exposing this safety liability during generic development in which normal, healthy volunteers are the test subjects. For these people, plasma concentrations will not lead to adverse events as they do in susceptible patients, the real target for the drugs in question.