Wellbutrin SR (bupropion hydrochloride sustained-release) is a second-generation antidepressant and aminoketone-class medication specifically formulated to address major depressive disorder. Unlike many conventional antidepressants that primarily affect serotonin pathways, Wellbutrin SR operates as a norepinephrine-dopamine reuptake inhibitor (NDRI), offering a distinct pharmacological profile with particular benefits for certain patient populations. This sustained-release formulation provides stable plasma concentrations over 12 hours, allowing for twice-daily dosing while maintaining therapeutic efficacy. Clinical evidence supports its use both as monotherapy and as an augmentation strategy in treatment-resistant depression.

Features

• Contains bupropion hydrochloride as the active pharmaceutical ingredient
• Sustained-release tablet formulation for controlled drug delivery
• Available in 100mg and 150mg tablet strengths
• White to off-white round tablets with functional score line
• 12-hour sustained release profile for consistent plasma levels
• NDRI mechanism targeting norepinephrine and dopamine reuptake inhibition
• Minimal serotonergic activity compared to SSRIs/SNRIs
• Manufactured under current Good Manufacturing Practices (cGMP)

Benefits

• Provides effective relief from depressive symptoms with a different mechanism than SSRIs
• Lower incidence of sexual dysfunction compared to serotonergic antidepressants
• Generally weight-neutral or associated with modest weight loss rather than gain
• Does not typically cause sedation, making it suitable for patients with fatigue or hypersomnia
• May improve concentration, energy levels, and motivation in depressed patients
• Reduced risk of discontinuation syndrome compared to some other antidepressants

Common use

Wellbutrin SR is primarily indicated for the treatment of major depressive disorder (MDD) in adults. It is also FDA-approved for the prevention of seasonal affective disorder (SAD). Off-label uses include attention-deficit/hyperactivity disorder (ADHD) management, particularly in patients who cannot tolerate stimulant medications or who have comorbid depression. Some clinicians prescribe it for smoking cessation support (though the XL formulation is specifically approved for this indication) and as an augmentation strategy when partial response occurs with other antidepressants. The medication may be particularly beneficial for patients who experience sexual side effects or weight gain with other antidepressant therapies.

Dosage and direction

The initial recommended dosage for Wellbutrin SR is 150mg administered once daily in the morning. After at least three days, the dosage may be increased to 150mg twice daily, with at least 8 hours between doses. The maximum recommended dose is 400mg per day, given as 200mg twice daily. Doses should be swallowed whole and not crushed, chewed, or divided, as this could damage the sustained-release properties and increase the risk of adverse effects including seizures. Dosage adjustments may be necessary for patients with hepatic impairment, elderly patients, or those taking concomitant medications that affect bupropion metabolism. Treatment should be initiated under close medical supervision, with regular assessment of therapeutic response and side effects.

Precautions

Patients should be monitored for emergence of anxiety, agitation, panic attacks, insomnia, irritability, hostility, aggressiveness, impulsivity, akathisia, hypomania, and mania. The risk of seizure is dose-dependent and increases at doses above 450mg daily. Caution is advised in patients with history of head trauma, prior seizure, central nervous system tumors, or concomitant medications that lower seizure threshold. Blood pressure monitoring is recommended as hypertension has been reported. Hepatic function should be assessed periodically, with dosage reduction in patients with moderate to severe hepatic impairment. Abrupt discontinuation should be avoided; taper gradually when discontinuing treatment. Patients should be advised regarding impaired ability to perform potentially hazardous tasks requiring mental alertness.

Contraindications

Wellbutrin SR is contraindicated in patients with seizure disorder or history of seizures. It should not be used in patients with current or prior diagnosis of bulimia or anorexia nervosa due to increased seizure risk. Concomitant use with monoamine oxidase inhibitors (MAOIs) is contraindicated, and a 14-day washout period must be observed when switching between these medications. Hypersensitivity to bupropion or any component of the formulation prohibits use. The medication is contraindicated in patients undergoing abrupt discontinuation of alcohol or sedatives (including benzodiazepines). It should not be used by patients with untreated or unstable epilepsy.

Possible side effects

Common adverse reactions (≥5% incidence) include dry mouth, nausea, insomnia, dizziness, pharyngitis, constipation, anxiety, agitation, and tremor. Less frequent side effects include tachycardia, hypertension, sweating, rash, weight loss, blurred vision, and taste perversion. Serious but rare adverse events include seizures (incidence approximately 0.4% at 300mg/day), allergic reactions, angioedema, Stevens-Johnson syndrome, hallucinations, psychosis, and suicidal ideation. The incidence of sexual dysfunction is notably lower than with SSRIs. Most side effects are dose-dependent and often diminish with continued therapy. Patients should report any unusual or severe symptoms promptly to their healthcare provider.

Drug interaction

Wellbutrin SR undergoes extensive metabolism primarily via CYP2B6, with minor contributions from other cytochrome P450 enzymes. Strong inhibitors of CYP2B6 (such as ticlopidine, clopidogrel) may increase bupropion exposure. Inducers of CYP2B6 (such as ritonavir, lopinavir, carbamazepine) may decrease bupropion levels. Bupropion inhibits CYP2D6 and may increase concentrations of drugs metabolized by this enzyme, including certain antidepressants (SSRIs, TCAs), antipsychotics (risperidone, thioridazine), beta-blockers, and type 1C antiarrhythmics. Concomitant use with other dopamine-affecting drugs may increase risk of adverse effects. Caution is advised with levodopa and amantadine. Alcohol consumption should be minimized due to increased seizure risk.

Missed dose

If a dose is missed, it should be taken as soon as remembered unless it is close to the time for the next scheduled dose. In that case, the missed dose should be skipped and the regular dosing schedule resumed. Patients should not take double or extra doses to make up for a missed dose, as this increases the risk of adverse effects including seizures. If multiple doses are missed, patients should contact their healthcare provider for guidance on resuming therapy. Consistent daily dosing is important for maintaining stable plasma concentrations and therapeutic effect.

Overdose

Bupropion overdose may result in seizures, hallucinations, loss of consciousness, sinus tachycardia, ECG changes (including QTc prolongation), and cardiac arrest. Fatal outcomes have been reported, particularly with large overdoses. Symptoms may include nausea, vomiting, drowsiness, and agitation. Management requires immediate medical attention with supportive care, including securing airway and maintaining cardiovascular function. Gastric lavage may be considered if presentation is early. Activated charcoal may be administered. Seizures should be treated with benzodiazepines; status epilepticus may require additional anticonvulsants. ECG monitoring is essential for at least 48 hours post-ingestion due to potential delayed effects.

Storage

Wellbutrin SR tablets should be stored at room temperature (20-25°C or 68-77°F) with excursions permitted between 15-30°C (59-86°F). The medication must be kept in its original container, tightly closed, and protected from light and moisture. Tablets should not be stored in bathroom cabinets or other humid locations. Keep out of reach of children and pets. Proper disposal of unused medication is important; unused tablets should not be flushed but rather disposed of through medication take-back programs or according to specific disposal instructions. Do not use beyond the expiration date printed on the packaging.

Disclaimer

This information is provided for educational purposes only and does not constitute medical advice. Wellbutrin SR is available by prescription only and should be used under appropriate medical supervision. Individual response to medication may vary, and treatment decisions should be made in consultation with a qualified healthcare professional based on individual patient circumstances. The complete prescribing information should be consulted before initiating therapy. Patients should report any adverse effects to their healthcare provider and adhere to prescribed dosage regimens.

Reviews

Clinical studies demonstrate Wellbutrin SR’s efficacy in major depressive disorder, with response rates comparable to other antidepressants but with a differentiated side effect profile. Many patients report preference due to lower incidence of sexual dysfunction and weight gain. Some note improved energy and concentration. However, some patients experience initial side effects including insomnia and anxiety that may diminish over time. The sustained-release formulation is generally well-tolerated with twice-daily dosing convenience. Overall satisfaction rates are favorable, particularly among patients who previously experienced undesirable side effects with serotonergic antidepressants. Long-term maintenance therapy shows sustained efficacy with appropriate monitoring.