Because of side effects is it ok for a 65 yr old woman to take 20 mg of prozac (fluoxetine) every other day?

Yes, but...: Prozac (fluoxetine) is a medication with a very long half life, which means it stays in your body for a long time and once at a stable level (which is 6 or 7 weeks for Prozac (fluoxetine) and it's active breakdown products) you can take these meds every other day. Of course why not 10mg a day? Or if the side effects are bad enough you may want to discuss changing medications? The goal is to feel better, not worse from SE's