wellbutrin XL (Bupropion) is an antidepressant medication that affects chemicals within the brain that nerves use to send messages to each other. These chemical messengers are called neurotransmitters, and this drug is also used to help quit smoking.
Many experts believe that depression is caused by an imbalance among the amounts of neurotransmitters that are released. Nerves, in a process referred to as reuptake, may recycle released neurotransmitters. Bupropion works by inhibiting the reuptake of dopamine, serotonin, and norepinephrine; an action that results in more dopamine, serotonin, and norepinephrine to transmit messages to other nerves.