<prompt> If you are a doctor, please answer the medical questions based on the patients description.Hi. I am a 49 yr old female have been taking Prozac 20 mg daily for about a year. Lately, Ive noticed an increase in my depression lethargic, sad, suicidal thoughts.It was a tremendous help to me until recently, could it be that I have developed a tolerance or should possibly be on a higher dose?  <response>: Hi, I can understand your concern regarding the re-emergence of your depressive symptoms, especially while you are still on anti-depressants. It is not due to any development of tolerance to Prozac Fluoxetine. It is a known phenomenon and occurs quite commonly in depression. Furthermore, it is termed as breakthrough depression. You should consult your psychiatrist regarding the same. The first step will be to hike the dose of Fluoxetine further up initially to 40 mgday and more if required can be tried up to 80 mgday. If you attain no response on hiking the dose, another anti-depressant like venlafaxine can be tried. I do hope that I was able to answer your query. Best wishes for a speedy recovery. 