My son has been taking prozac (fluoxetine) for 12 yrs and has titered down to 20 mgs every three days to see if he can do without it. is this wise?

Yes: Re-evaluating the need for a medication under the direction of a physician is always wise. If his physician knows about the decrease in the medication and is helping evaluate the results, it should be fine. Why take medications that you no longer need?

Of course, you care: And it is so wonderful that a father really cares that I hesitate to affect it. But this has to be decided by your son and the psychiatrist. 12 years is very long. There are many happy reports of this plan. How is your son at this level? Let that be your general source of comfort if it is generally good. From what I hear, it can up increased briefly if there are tough spots. Work w/ the provider.