You are right. It’s not all that common to gain on SSRI meds. I believe 1-6% is the average in those prone. (Directly and indirectly from the medication). As a psych professional I haven seen as much as with anti psychotics which can be 10-50 pounds on average. Wellbutrin is thought to cause least chance of weight gain. Everyone is different though, you’re right. Could try a different SSRI like Prozac or SNRI like viibryd. Talk to doc. It could be life style issue like sleep, exercise, feeling hungry when not depressed. The body is a mysterious entity.

Moving to another drug--Trintellex--these past two weeks. Already losing weight!