What is Wellbutrin? Wellbutrin is the brand name for bupropion and the active ingredient in Wellbutrin is bupropion hydrochloride (bupropion HCl). It’s commonly used to treat major depression and seasonal affective disorder or SAD. It’s also used to aid in smoking cessation. Wellbutrin XL and Wellbutrin SR are different formulations of the antidepressant bupropion. Both Wellbutrin XL and Wellbutrin SR may cause weight gain or weight loss, but weight loss is more common. Bupropion is used to treat major depressive disorder (MDD) and to prevent seasonal affective disorder (SAD), which is sometimes called autumn-winter seasonal depression. It is also used as part of a support program to help people stop smoking. Bupropion is sold under different brand names. Wellbutrin (bupropion) used to treat the symptoms of major depression and seasonal affective disorder. Learn side effects, dosage, drug interactions, warnings, patient labeling, reviews, and more. Wellbutrin is used to treat major depressive disorder and seasonal affective disorder. Common side effects of Wellbutrin include headaches, dry mouth, nausea, dizziness, insomnia, and constipation. Call your doctor if you experience serious side effects such as difficulty breathing or swelling. Wellbutrin (bupropion) is an FDA-approved antidepressant medication that treats health conditions such as depression and seasonal affective disorder. Common Wellbutrin side effects include tremors, agitation, and dry mouth. Find patient medical information for Bupropion (Wellbutrin, Zyban, and others) on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user ratings Wellbutrin (bupropion) is used to treat major depressive disorder and seasonal affective disorder. Includes Wellbutrin side effects, interactions and indications. Bupropion (Wellbutrin) treats depression. It helps regulate your mood by increasing norepinephrine and dopamine hormones in your brain. The FDA investigated these complaints and concluded that Budeprion XL is equivalent to Wellbutrin XL regarding bioavailability of bupropion and its main active metabolite hydroxybupropion.