PCL201H1 Lecture : Lecture 21 Variability – Role of Pharmacogenetics
Document Summary
Prescribed drugs are generally effective in about 50% of patients. Inappropriate prescriptions adverse reactions (adrs) death. Cost of treating adrs > cost of medications themselves. Current trial and error method of drug prescribing. Gnenetically-enabled personalized medicine : use genetic technology to develop better medications, predictive genotype tests to determine ideal dose, drug, in right patient at right time. Variation in drug response: genetic and environmental factors contribute to adme. Pharmacogenetics: study of influence of genetic factors on response to and toxicity of foreign chemicals. Patients with same diagnosis may not be homogenous; may require different treatments. Need technology to identify segregation of: responders who are not predisposed to toxicity (given conventional drug/dose), and non-responders who are toxic responders (require alternative drug/dose) Snps correlate with disease predisposition, influence response to medications. Classification of pharmacogenetic variants: pharmacologic, pharmacokinetic: body drug, pharmacodynamic: drug body, monogenic, genetic. Pharmacogenetics of drug metabolism: variation in how body hits drug.