The FDA already has approved Prozac in a daily dosage. Some continued taking the daily doses, while others in the group were switched to the weekly Prozac or a dummy pill, called a placebo, which is used for comparison. Both groups that took the Prozac formulations did much better than the placebo group. The people taking the daily antidepressant formula had a slightly better relapse rate than the weekly group, but the researchers concluded the difference was not significant. The FDA did not require the manufacturer to extensively compare the weekly vs. the daily doses of the drug.
Depression treatment lasts a long time.
Even when patients start feeling better, they still need to be taking their medicine so their condition will continue to improve. But some patients may grow tired of taking a daily antidepressant and stop after they begin feeling better, only to have their depression relapse. Some doctors believe that patients will be more likely to follow through with their treatment if they need to take only a weekly pill. Doctors still are not sure how this new dosage will compare to the daily version of Prozac, so it's not known how many people switching to the weekly dosage will suffer a relapse of their depression. The FDA advises that doctors should switch a patient back to the daily dose of Prozac if it looks like control of the disease begins to slip.