25 - Biological treatments: general considerations

Summary

This chapter on general considerations for biological treatments in psychiatry covers four main areas: pharmacokinetics, pharmacodynamics, behavioural pharmacology and pharmacogenetics. Within each of these, general principles are defined, and examples relevant to psychiatry provided. Drugs exert their pharmacological, physiological and behavioural effects by interacting with either extracellular or intracellular target sites. Interpatient variability can result from differences in rates of drug absorption and metabolism, as well as multiple other factors, including previous drug use and physical, psychological and emotional state. The recent completion of the mouse and human genomic sequences has greatly facilitated research in genomics and proteomics. Pharmacogenomics aims to develop novel diagnostics accompanying therapeutic products for effective and safe individualised drug prescription. Both fields therefore hold great potential, particularly in psychiatry, for which biologically based treatment guidelines are lacking. The ethical issues that arise from pharmacogenetic research should be addressed before the benefits from treatment individualisation are realised.