If you run out of prozac, (fluoxetine) how long do you have before you get Prozac (fluoxetine) withdrawal?

It depends. Prozac (fluoxetine) has active metabolites that have similar effect as prozac (fluoxetine). These breakdown chemicals will attenuate withdrawal effects, theoretically delaying withdrawal, if any. These effects may be present for several days to as long as two weeks. Make an effort to promptly renew your prescription and contact your physician.