Brad,
As a Dr. you should know that side effects are an important part of the decision process when the FDA considers whether a drug offers added benefits to the currently available treatment. Yes, there is often no way to determine patient to patient variability in terms of efficacy. However, there is clearly a way to determine added benefit through the extent and type of adverse side effects. Zoloft, for example, has been shown to cause headaches in 20.3% of the patients who take it, male impotence in 15.5% of the male patients who take it, and somnolence in 13.4% of the patients who take it. Plaxil, by comparison, will cause somnolence in 12.7% to 21.6% of the patients depending on the dose, impotence in 1.5% of patients, and 0% incidence of headaches. Clearly, there are subsets of the patient population that can gain a maximum benefit from taking one or the other but not both and these differences are easily defined prior to FDA approval. The same is true over every other drug in very other class.
Hank |
