Hi, Different side effects or gaining weight in particular depends entirely on how your body reacts to the medication. It is possible that you will notice no change in weight or that you will swing in the opposite direction of what s typical, no matter which medication you take. For some people, the fluctuation in weight is only temporary. You may be surprised to learn that there are two antidepressants linked to weight loss. These two are prozac and wellburtin. Prozac increases the levels of serotonin in the brain and these are generally the first-line treatment for depression. Any weight loss you may experience while taking Prozac may only be temporary and weight gain after the first few months may be possible. Wellbutrin is an atypical antidepressant that doesn t change serotonin levels in the brain. Rather, it uniquely alters other brain chemicals like noradrenaline and dopamine. This is associated not only with weight loss but also improved sexual functioning. Like all antidepressants, Wellbutrin and Prozac carry a black box warning. This states their potential for increased risk of suicidal thoughts and actions in children, teens, and young adults during the early stages of treatment. So it ultimately comes down to your doctor.Have a candid discussion with your doctor about depression treatment as there are a lot of options out there. If you have concerns about weight loss or gain, talk to your doctor about diet and exercise changes you can make as well. By changing a few habits and feeling healthier, you can also improve your emotional and mental health. Hope I have answered your query. Let me know if I can assist you further. Regards, Dr. Prabhash Verma, General & Family Physician