Hi
The most common side effects associated with escitalopram are agitation or
restlessness,
blurred vision, diarrhea, difficulty sleeping, drowsiness, dry mouth, fever,
frequent urination, headache,
indigestion, nausea, increased or decreased appetite, increased sweating, sexual difficulties (decreased sexual ability or desire, ejaculatory delay), taste alterations, tremor (shaking), and weight changes.
My understanding is the weight gain from this medication is not permanent and it should go away if you reduce the dose or stop it, although the problem is if it helping you so much with the anxiety it may be very difficult to do .
Please check your thyroid levels regularly and adjust the dose according to your doctor's advise, eat a low calorie food and have lot of physical activity, this should help in
weight loss as well as in anxiety/depression.