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Uses & FDA Indications

Bupropion carries FDA approval for major depressive disorder (MDD), seasonal affective disorder (SAD), and smoking cessation (as Zyban). Its unique dopaminergic mechanism makes it especially useful for patients who experience significant fatigue, cognitive slowing, or sexual dysfunction on serotonergic antidepressants.

Off-label applications include attention-deficit/hyperactivity disorder (ADHD), bipolar depression (as an adjunct to mood stabilizers), and as an add-on to SSRIs to counteract sexual side effects or augment antidepressant response. Contrave, a combination of bupropion and naltrexone, is FDA-approved for chronic weight management.

How It Works

Bupropion inhibits the reuptake of both norepinephrine and dopamine, increasing the synaptic availability of these neurotransmitters. It has no clinically meaningful effect on serotonin, which is why it lacks the sexual side effects and weight gain associated with SSRIs and SNRIs.

For smoking cessation, bupropion's dopaminergic activity is thought to reduce the rewarding effects of nicotine by modulating the mesolimbic dopamine pathway. It also acts as a non-competitive antagonist at nicotinic acetylcholine receptors, which may independently reduce nicotine craving and withdrawal symptoms.

The drug is a prodrug that is hepatically metabolized to several active metabolites, most notably hydroxybupropion, which is a potent norepinephrine reuptake inhibitor and may account for much of the antidepressant effect. These metabolites accumulate with repeated dosing, necessitating gradual initiation to reduce seizure risk.

Side Effects

Common

• Insomnia or vivid dreams (take doses earlier in the day to mitigate)
• Dry mouth
• Headache
• Nausea
• Agitation or anxiety
• Increased heart rate (mild tachycardia)
• Constipation
• Tremor

Serious

• Seizures — dose-dependent risk; most significant distinguishing safety concern
• Suicidal ideation — black box warning in patients under 25, and additional warning for neuropsychiatric effects with smoking cessation use (Zyban)
• Neuropsychiatric events — agitation, hostility, depressed mood, and behavioral changes reported with smoking cessation treatment
• Hypertension — monitor blood pressure before and during treatment
• Psychosis or mania — can precipitate in susceptible individuals
• Angle-closure glaucoma — mydriatic effect may trigger acute attack in predisposed patients

Drug Interactions

Drug / Class	Interaction	Clinical Significance
MAO Inhibitors	Severe hypertensive reactions and seizure risk	Contraindicated — 14-day washout required
CYP2D6 substrates (metoprolol, antipsychotics, TCAs)	Bupropion inhibits CYP2D6, raising levels of co-medications significantly	High — dose adjustment of the co-medication may be needed
Other seizure threshold-lowering drugs (tramadol, antipsychotics, theophylline)	Additive seizure risk	High — avoid combination or use with extreme caution
Alcohol	Increased seizure risk; may worsen neuropsychiatric effects	High — minimize alcohol use; abrupt withdrawal from heavy use is a contraindication
Dopaminergic drugs (levodopa, amantadine)	Additive dopaminergic effects; increased side effects	Moderate — use cautiously
Nicotine replacement therapy	May increase blood pressure when combined with nicotine patches	Moderate — monitor BP
Clopidogrel	CYP2D6 inhibition may reduce conversion to active metabolite, reducing antiplatelet efficacy	Moderate

Warnings & Contraindications

Contraindications: Seizure disorder or any condition that predisposes to seizures. Current or prior diagnosis of anorexia nervosa or bulimia nervosa (associated with higher seizure incidence). Abrupt discontinuation of alcohol, benzodiazepines, or antiepileptics. Concurrent use of MAO inhibitors. Known hypersensitivity to bupropion.

Seizure risk: Bupropion lowers the seizure threshold in a dose-dependent manner. Risk is significantly increased by factors such as eating disorders, head trauma, CNS tumors, heavy alcohol use, and concurrent seizure threshold-lowering drugs. The extended-release formulations (SR, XL) have a lower peak serum concentration and thus lower seizure risk than the immediate-release form.

Avoid crushing or chewing: Extended-release tablets must be swallowed whole. Breaking, crushing, or chewing them results in rapid drug release and significantly elevated seizure risk.

Frequently Asked Questions

Why doesn't bupropion cause sexual side effects?

Sexual dysfunction from SSRIs and SNRIs is largely attributable to excess serotonin activity, which inhibits dopamine pathways involved in sexual arousal and response. Because bupropion works on norepinephrine and dopamine without affecting serotonin, it avoids this mechanism. Some patients even experience improved sexual function compared to baseline.

Can bupropion cause weight loss?

Bupropion can suppress appetite and is associated with modest weight loss or weight neutrality, in contrast to SSRIs which more commonly cause weight gain with long-term use. However, it is not prescribed solely as a weight loss drug — except in the form of Contrave (bupropion/naltrexone), which is FDA-approved for weight management.

Is bupropion effective for ADHD?

While not FDA-approved for ADHD, bupropion is considered a second-line option when stimulant medications are not tolerated, contraindicated, or ineffective. Its dopaminergic and noradrenergic effects are mechanistically similar to stimulant medications, and clinical evidence supports its utility in ADHD management in both adults and children.

How does bupropion help people quit smoking?

Bupropion was originally approved as an antidepressant and was serendipitously found to reduce nicotine cravings. It works by blunting the dopamine reward from cigarettes and reducing withdrawal symptoms through nicotinic receptor antagonism. It is typically started one to two weeks before a planned quit date.

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