That's a little unusual. Most people don't get withdrawal symptoms with Prozac bc you're right, it has a ridiculously long half life. It can actually be used to help with withdrawals from other SSRIs. I can see how the one day on, one day off etc might kind of throw you for a loop. If it was me, I'd ask for some 10 mg tabs and taper down to 10 mg/day, then completely stop. You're on 20 mg? Maybe stay on that for a week, then 10 mg for a week? That's what I'd do anyway. Just an idea. Sorry you're so miserable.