Abstract
The principle of the microdialysis technique, the microdialysis system and its application to pharmacokinetic studies is discussed. By applying the microdialysis technique to pharmacokinetic studies the number of animals needed can be substantially reduced, because the technique involves a sampling technique which does not withdraw body fluid and so does not disturb blood homeostasis. Therefore, there are no limiting factors to the amount of samples taken from one animal. The utility offered by the microdialysis technique will have a bearing on future pharmacokinetic studies and it is to be expected that the importance of microdialysis in pharmacokinetic studies will grow in the future.