Antidepressants have a bad reputation for causing weight gain. While this is true for many of them, there are also several drugs that can lead to weight loss. Antidepressants cause weight gain in one of two ways: they increase appetite or they affect metabolism. According to Dr. David L. Katz in an article for O, the Oprah Magazine, if you're taking antidepressants and can't seem to lose weight, try eating more fiber-rich foods to keep you full without adding too many calories, or ask your doctor about switching to an antidepressant that can actually help with weight loss.
Bupropion, sold under the brand name Wellbutrin, causes weight loss in up to 28 percent of people who take it, according to eMedTV. The average person loses 5 lbs. or more when taking bupropion. Bupropion can lead to weight loss in a number of ways. For example, the drug may cause nausea and a loss of appetite, naturally causing you to eat less. The weight loss is likely to stabilize after some months. If you're losing too much weight, talk to your doctor.
One of the side effects of venlafaxine is weight changes. In many cases, this means a weight loss of 1 to 2 lbs, although some people gain weight while taking venlafaxine. According to eMedTV, some people can lose a considerable amount of weight on venlafaxine, which can be a problem if you're already within your desirable weight range.
Selective Serotonin Reuptake Inhibitors (SSRIs)
Selective serotonin reuptake inhibitors (SSRIs) are a group of antidepressants that includes well-known drugs such as sertraline (Zoloft), escitalopram (Lexapro) and citalopram (Celexa). Paroxetine (Paxil) is also an SSRI but it's known to cause weight gain, according to MayoClinic.com. SSRIs cause weight loss in some people and weight gain in others. If you haven't had luck losing weight with bupropion and venlafaxine, your doctor might recommend that you try an SSRI.
Serotonin-Norepinephrine Reuptake Inhibitors (SNRIs)
Serotonin-norepinephrine reuptake inhibitors (SNRIs) is a group of drugs used to treat not only depression but also anxiety and other mood disorders. Venlafaxine belongs to this group of drugs. Other SNRIs include desvenlafaxine (Pristiq), duloxetine (Cymbalta) and milnacipran (Savella). The weight-loss drug sibutramine, sold under the brand name Meridia, is actually a SNRI. This group of drugs act by affecting the area of the brain that controls appetite and satiety levels, controlling cravings and reducing your impulse to overeat.