Pharmacogenetics in clinical practice

The availability of data from pharmacogenetic studies is reflected in therapeutic practice, and pharmacogenetics is slowly entering the medical arena. Preconditions for the utilisation of pharmacogenetic knowledge are that:1) genetic variation and prevalence are known2) pharmacological consequences (concerning efficacy or toxicity) are known3) clinical relevance is demonstrated4) data from pharmacogenetic studies are translated in to practical guidelines5) knowledge and techniques are available.Tasks and responsibilities should be clearly set out regarding the request for pharmacogenetic analysis, the pharmacogenetic analysis itself, interpretation of the results and advice to the medical practitioner. The advice to give or not to give a drug to a patient, or to adjust drug dose or frequency, cannot be based exclusively on someone's genotype, but is the result of several factors. These include age, sex, weight, liver and renal function, concomitant medication, drug blood levels, serum albumin and protein binding, whether the patient smokes, nutrition and genetic factors (a combination of several genotypes).Pharmacogenetics will be an important and useful tool for individualising pharmacotherapy in the near future, as is therapeutic drug monitoring at present. The first examples of pharmacogenetic knowledge in medical practice are already in use.