How long does Fluoxetine take to work?


Well-known member
My GP had prescribed me fluoxetine 7 weeks ago. I started on 10mg for the first four days, then 20mg until I hit four weeks. Since then, my doctor has upped the dosage to 40mg.

I haven't had any significant side effects, but I'm also not really feeling much difference in my anxiety either. I was told that it generally takes 2-4 weeks for benefits to come around but can take up to 8 weeks. I believe I might've felt better at about the 4 week mark, since that's when I was expecting the meds to kick in but it could've also been a placebo effect. At 7 weeks, I'm not particularly optimistic on whether fluoxetine is going to work.

So if you've had success with fluoxetine, how long did it take for it to kick in?
Any opinions on whether I should continue (I could just be an exception to the norm) or perhaps try a new medication when I see the doctor next week?


New member
i didn't do well on it. my last psych did the same thing with a different antidepressant (slowly upping the dose). it's safest. definitely talk to your doctor about it, though. they might suggest a new medication or upping the dose.


Generally speaking, the SSRI's will begin to kick in at around 2 weeks and achieve maximum efficacy by 4-6 weeks. You did not indicate what dose you are on, but be aware that the efficacy is often dose-related. Some people with mild symptoms achieve an adequate therapeutic response at low doses, for others they may not achieve full or immediate relief until the dose is raised. Just a word of caution here if you are receiving your meds through your primary doc-it's been my experience that primary docs are often hesitant to raise dosages to therapeutic levels and often discard a medication as not working simply because they have not given it an adequate trial and are prescribing at sub-therapeutic levels. Talk with your doc about your dosage and what the ceiling dose is and if you are feeling some effect, but not enough, ask them to consider raising the dose before assuming the med isn't working adequately.