bupropion
Meaning of bupropion: Chosen as often for what it does not do, since weight gain and sexual side effects are less common than with serotonin antidepressants.
Definition of bupropion
Bupropion is an antidepressant that acts on norepinephrine and dopamine rather than serotonin, which sets it apart from the selective serotonin reuptake inhibitors. It is prescribed for depression, including the seasonal pattern, and under a separate brand name as an aid to stopping smoking. It is also added to another antidepressant when one alone has not been enough.
How is it different from an SSRI?
| Bupropion | Serotonin reuptake inhibitors | |
|---|---|---|
| Main target | Norepinephrine and dopamine transporters | The serotonin transporter |
| Sexual effects | Uncommon | Common and often persistent |
| Weight | Neutral or slight loss | Gain in some people over time |
| Sedation | Activating; can disturb sleep | Varies, often sedating early on |
| Anxiety | May worsen it in some people | Effective for several anxiety disorders |
These contrasts are the reason it is chosen after another antidepressant has worked but produced an unacceptable side effect, and the reason the two are sometimes combined.
Why does it help with smoking?
Nicotine acts on the same dopamine reward pathway that bupropion influences, and the drug also blocks nicotinic receptors directly. The result is a reduction in craving and in the irritability, restlessness and low mood of withdrawal. It is started one to two weeks before the planned quit date so that levels are established when smoking stops, and it works whether or not the person is depressed, which shows the effect is not simply a lifting of mood. The dose and brand name used for this purpose differ from those used for depression, and the two products are not taken together because the active ingredient is the same.
What limits its use?
Bupropion lowers the threshold at which a seizure occurs. The risk is dose-related and small at standard doses, but it means the drug is not used where a seizure disorder is present, where an eating disorder such as bulimia or anorexia has occurred, or where a person is stopping alcohol or sedatives abruptly, since all of these independently raise seizure risk. Insomnia, dry mouth, headache, agitation and raised blood pressure are the common effects, and the activating quality that suits some people unsettles others. Like all antidepressants it carries a warning about suicidal thinking in young people early in treatment. Acting on norepinephrine and dopamine rather than serotonin also means it does not treat the anxiety disorders that serotonin drugs address.
Also known as
Used in a sentence
Bupropion was prescribed to support the patient's efforts to quit smoking.
Good to know
Bupropion works through a different mechanism than the selective serotonin reuptake inhibitors, which is why it is sometimes selected for a person who has not tolerated or responded to that class.