Pharmacology 2060A/B Lecture Notes - Lecture 9: Median Toxic Dose, Therapeutic Index, Frequency Response
Document Summary
In an ideal world the response to medications would be the same for every patient. Because response to medications is variable, every patient"s response must be evaluated to ensure an adequate therapeutic response. Unfortunately in reality, response to medications is quite variable between patients. The response to medication is influenced by genetics, disease state, and the environment. Clinical trials are an important first step in determining interpatient variability to drug response. Phase ii clinical trials establish dose response information over a range of doses. To determine interpatient variability in response to medications, we first set an endpoint. For example, if we were talking about an analgesic drug, the endpoint would be pain relief. From phase ii clinical trial data we can evaluate the number of patients that experience pain relief from each dose of the drug. This data is plotted on a frequency distribution curve. The average effective dose (ed50) is at the peak of the frequency distribution curve.