title: [Medical problems in the practical execution of drug testing].
abstract: Different experimental designs for a clinical trial have to be applied for every individual substance even if it, though closely related to some other, shows minor differences in its effects. Difficulties which often occur during phase I trials are: the choice of the volunteer, dosage and route of application of the substance, especially in the first trials in humans, the instructions to the volunteer after intake of the drug, increase in dosage, the number of repeating applications and the interval between uptake. Problems arising during phase II, III and IV trials are concerned mainly with controlled clinical trials: choice of the standard treatment or of a placebo, search for the influencing factors, etiology of the symptoms, stage of the illness, control of patient's compliance etc. In contrast to common opinion, clinical trials cannot be considered to be especially dangerous as data show.
mesh_terms: D000367:Age Factors; D001682:Biological Availability; D002986:Clinical Trials as Topic; D004341:Drug Evaluation; D004992:Ethics, Medical; D005247:Feeding Behavior; D006801:Humans; D007258:Informed Consent; D007700:Kinetics; D010919:Placebos; D012107:Research Design; D013045:Species Specificity
chemical_list: D010919:Placebos
vernacular_title: Arztliche Probleme bei der praktischen Durchführung von Arzneimitteltestungen