As you can see, Effexor is amongst the least likely to cause
weight gain,
and in fact, is known to contribute to
weight loss. You may wish to try an alternative on the list above.
It is unclear why anti-depressants cause weight gain. Here are some possibilities:
• Overeating, as a result of depression, can cause weight gain, esp if the person had lost weight in the pretreated depression
• Most anti-depressants, mood stabilizers and antipsychotics are also anti-histamines.