Pharmacokinetic aspects of optimal pain treatment.

The number of scientific papers dealing with pharmacokinetic investigations has grown almost exponentially during recent years. The resulting characterization of the kinetics of many drugs has given us a firm basis for a more effective and rational drug treatment. However, pharmacokinetic studies on narcotic analgesics have been less numerous, mainly due to the lack of suitable chemical methods for analyses of these drugs. The new specific and sensitive techniques (e.g. gaschromatography-masspectrometry and gaschromatography with electron capture detectors) have been found suitable for determination of several of the opiates in biological tissues. This paper describes some aspects of the development of the pharmacokinetic discipline and how we should use the kinetic information obtained for optimal pain treatment and a better understanding of the mechanism of action of the opiates.