Although cannabis is especially known for its recreational use as a __soft drug__, its potential therapeutic properties have been recognized for hundreds of years. Since the isolation of THC from... Show moreAlthough cannabis is especially known for its recreational use as a __soft drug__, its potential therapeutic properties have been recognized for hundreds of years. Since the isolation of THC from Cannabis sativa L, the discovery of cannabinoid receptors and their natural ligands (endocannabinoids) the interest in the development of novel cannabinoids as medicine is accelerating. This thesis describes useful cannabis-biomarkers and the clinical pharmacology of some cannabinoid agonists and antagonists in early phase drug development. This includes a novel mode of pure intrapulmonary THC administration that can be used as a benchmark for novel CB1/CB2-agonists, or to demonstrate inhibitory activity of CB1-antagonists. In addition, the pharmacodynamics and pharmacokinetics of two novel CB1/CB2 agonists are evaluated and compared with the pharmacodynamic effect profile of THC. The clinical trials carried out for this research were performed at the Centre for Human Drug Research, Leiden, The Netherlands. Show less
The overall goal was to develop individualized dosing guidelines for the sedatives propofol and midazolam in infants and in critically ill patients, on the basis of population pharmacokinetic... Show moreThe overall goal was to develop individualized dosing guidelines for the sedatives propofol and midazolam in infants and in critically ill patients, on the basis of population pharmacokinetic-pharmacodynamic (PK-PD) modeling. Both under- and oversedation significantly and adversely affects patient outcome. Due to the high intra- and interindividual variability in dose requirements dosing is complicated. In this thesis the interindividual variability in response has been examined by covariate analysis. In this analysis the effects of bodyweight, cardiac function, severity of illness and liver blood flow and the unexplained interindividual variability have been characterized. It was shown that infants require higher doses of propofol because of differences in pharmacokinetics rather than pharmacodynamics. When comparing the results of the PK-PD model of propofol and midazolam in infants, propofol is preferred over midazolam because of the lower interindividual variability in pharmacodynamics compared to midazolam. In critically ill patients severity of the illness was found to be a major determinant of the level of sedation, with lower propofol dosing requirements with increasing severity of illness. The PK-PD models can be used as a basis for individualized dosing of propofol and midazolam, which is essential for optimizing the quality of sedation in clinical practice and will improve patients__ outcome. Show less