Experimental gerontological research is necessary to obtain optimal information and thus ensure proper drug therapy for the elderly. Most older persons acquire multiple diseases, first of all chronic diseases. They involve complex problems of a physical, social, and psychological nature. The multimorbidity of the elderly raises many questions in drug therapy. By contrast with our extensive knowledge of pharmacokinetics and pharmacodynamics in younger age groups, few facts are available in respect of the elderly. A variety of factors may influence drug therapy. Physiological and pathological...