Zoloft can also be a stimulant but it depends on how long you are taking the medication. If you have been taking it since April, that effect should have worn off long ago and you should think of switching to some other antidepressant. Paxil Cr is less likely to cause weight gain. Wellbutrin is another to try.
You and your doctor should consider increasing the dose of zoloft only if you think the cause of your anxiety is not the medication( whatever the underlying cause is). That is called breakthrough anxiety.
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