Prozac and Zoloft are potent antidepressant medicines. They're both brand-name medications. Prozac's generic name is fluoxetine, while Zoloft's generic name is sertraline hydrochloride. Both medications act as selective serotonin reuptake inhibitors (SSRIs). That means they work by increasing the amount of serotonin available for nerve cells to receive, which in turn reduces symptoms of depression. Both Prozac and Zoloft must be taken orally, usually once a day. However, zoloft can be taken at any time during the day or night, while prozac must be taken within an hour before going to bed. Taking zoloft late in the evening may decrease its effectiveness as well as pose problems for those who drive motor vehicles while under its influence. Neither Prozac nor Zoloft is approved for children under 18 years old. However, both are commonly used with children and adolescents. Studies have shown that up to 90% of adults who suffer from major depressive disorder (MDD) also suffer from some form of childhood anxiety disorder. This suggests that MDD may actually be present in almost all cases of adult-onset anxiety. In addition, research has shown that people who take SSRIs for more than one year experience fewer side effects over time. These studies suggest that regular use may create a tolerance for these drugs so that higher doses are needed over time.