How long does 10mg of prozac (fluoxetine) take to get into your blood system to feel effects?

Prozac (fluoxetine): The time to onset of action of an antidepressant, including prozac, (fluoxetine) depends upon a number of factors including the condition being treated. That being said, you can generally expect one to two weeks to start to notice the clinical effect and 4-6 weeks to safely evaluate the full effect of any particular dose in the treatment of depression. Side effects, if present, can be experienced sooner.