I've been on citalopram 10mg for the past week now, have felt nauseous on and off all week and my appetite has also decreased! Have been feeling really low all day today and have a feeling of never ending gloom. Just feel really lost at the moment! Doesn't help that i've had a few sleepless nights with a poorly little one! I know that lack of sleep affects my mood. How long does it normally take to start feeling the effects of AD's?