“…Many examples of the age‐related changes in tissue function and morphology which influence drug activity and efficacy have been provided by other authors (1, 3–6, 8–12); these are based on studies of various aspects of aging and the aging process (7, 8, 14, 15, 19–39). Though it is not difficult to postulate age‐related changes in drug activity, the direction and magnitude of alterations in the response are not so easy to predict because of the many variables which influence drug activity.…”