Prozac has a very long half-life, relative to any other antidepressant. If you just started on Prozac, then the half-life is somewhere between 1 and 3 days. But, because Prozac self-inhibits, if you've been on Prozac a while, the half-life goes to 4-6 days.

In practical terms, that means that if you're taking Prozac daily, you could miss a dose and not even notice.

During withdrawal, that means that the drug actually tapers itself. Natural elimination of Prozac and its metabolites *might* go so slowly that you don't even get withdrawal symptoms.

However, prudence would suggest that you reduce the dose by halves, weekly, until you are down to 5-10 mg. Then, you can probably go cold turkey without problems. If symptoms of withdrawal do arise after that, you can take 5 mg once in a while, to make the taper even more gradual.

One potential drawback to using Prozac is that if you're switching drugs, you may have to go a long time unmedicated, to clear all the Prozac out of your body.

Best,
Lar