That's a great question. Everybody's response to meds like citalopram vary. Some people experience total remission (no symptoms left), while others improve but still have residual symptoms. Remember, the goal is not to be smiling & happy 24/7...that's not realistic for the most part. Life is made of ups & downs.
What you want to do is look at patterns. If you have been on 20mg for over a month and just having an occasional bad day or rough night sleep, there may be no reason to change things. If you feel 80% better or less than before the medicine, you could certainly try 30-40mg (after double checking with your own doctor, of course) to see if you do better at that dose. Keep in mind, every time you increase a dose you could develop side effects (luckily, citalopram is quite gentle overall).
Also remember there are other things you can do with the meds to treat depression: psychotherapy, nutrition, exercise, relaxation therapy, & self-help books. Let me know if you need further details. Good luck & take care.
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