Wellbutrin XR®

Bupropion hydrochloride

What is Wellbutrin?
Mechanism of action
How to prescribe Wellbutrin XR

For full information, please see the Summary of Product Characteristics.

What is Wellbutrin?

There appears to be a pattern of symptoms that are inadequately addressed by serotonergic antidepressants - loss of pleasure, loss of interest, fatigue and loss of energy.3

Evidence suggests that symptoms of decreased positive affect might be mediated by the dysregulation in noradrenergic and dopaminergic neurotransmitters.3

Wellbutrin (bupropion) is a selective inhibitor of the neuronal re-uptake of catecholamines (noradrenaline and dopamine) with minimal effect on the re-uptake of indolamines (serotonin) and does not inhibit either monoamine oxidase.9

Wellbutrin XR offers a different treatment approach through the unique dual mode of action combining Noradrenaline and Dopamine Re-uptake Inhibition (NDRI).1,2


WELLBUTRIN XR is indicated for the treatment of major depressive episodes.9

Mechanism of action

The mechanism of action of bupropion as an antidepressant is unknown. However, it is presumed
that this action is mediated by noradrenergic and/or dopaminergic mechanisms.9

How to prescribe Wellbutrin XR

The recommended starting dose is 150 mg, given once daily. If no improvement is seen after 4 weeks treatment at 150 mg, the dose may be increased to 300 mg, given once daily. There should be an interval of at least 24 hours between successive doses.9

Patients with major depression should be treated for a sufficient period of at least 6 months to ensure that they are free from symptoms.9

Morning dosing is recommended (Insomnia is a very common adverse event which is often transient. Insomnia may be reduced by avoiding dosing at bedtime).9

For full information, please see the Summary of Product Characteristics.


  • hypersensitivity to bupropion or any of the excipients
  • taking any other medicinal product containing bupropion, as the incidence of seizures is dose dependent and to avoid overdosage
  • with a current seizure disorder or any history of seizures
  • with a known central nervous system tumour
  • who, at any time during treatment, are undergoing abrupt withdrawal from alcohol or any
    medicinal product known to be associated with a risk of seizures on withdrawal (in
    particular benzodiazepines and benzodiazepine‐like agents)
  • with severe hepatic cirrhosis
  • with a current or previous diagnosis of bulimia or anorexia nervosa

Concomitant use of WELLBUTRIN XR and monoamine oxidase inhibitors (MAOIs) is
contraindicated. At least 14 days should elapse between discontinuation of irreversible
MAOIs and initiation of treatment with WELLBUTRIN XR. For reversible MAOIs, a 24 hour
period is sufficient.9

The recommended dose of modified release bupropion tablets should not be exceeded,
since bupropion is associated with a dose‐related risk of seizure. The overall incidence of
seizure with modified release bupropion tablets in clinical trials at doses up to 450 mg/day
was approximately 0.1%.9

Very common side effects with Wellbutrin XR use include be insomnia, headache, dry mouth,
gastrointestinal disturbance including nausea and vomiting.9


  1. Fava M, Rush AJ, Thase ME, Clayton A, Stahl SM, Pradko JF, et al. 15 years of clinical experience with bupropion HCl: from bupropion to bupropion SR to bupropion XL. Prim Care Companion J Clin Psychiatry 2005; 7:106–13.
  2. Stahl SM, Pradko JF, Haight BR, Modell JG, Rockett CB, Learned‐Coughlin S. A Review of the Neuropharmacology of Bupropion, a Dual Norepinephrine and Dopamine Reuptake Inhibitor. Prim Care Companion J Clin Psychiatry 2004;
    6: 159–66.
  3. Nutt DJ, Demyttenaere K, Janka Z, Aarre T, Bourin M, Canonico PL, et al. The other face of depression, reduced positive affect: the role of catecholamines in causation and cure. J Psychopharmacol 2007; 21: 461–471.
  4. Stahl SM. Essential Psychopharmacology.
  5. Foote SL, Aston‐Jones GS. Chapter 29. Pharmacology and physiology of central noradrenergic systems. In: Bloom FE, Kupfer DJ, editors. Psychopharmacology: the fourth generation of progress. New York: Raven Press Ltd; 1995.
    p. 335–45.
  6. Shelton RC, Tomarken AJ. Can recovery from depression be achieved? Psychiatr Serv 2001; 52: 1469–78.
  7. Stahl SM. Deconstructing psychiatric disorders, part 2: An emerging, neurobiologically based therapeutic strategy for the modern psychopharmacologist. J Clin Psychiatry 2003; 64: 1145–6.
  8. Nutt DJ. Relationship of neurotransmitters to the symptoms of major depressive disorder. J Clin Psychiatry 2008;
    69 Suppl E1:4–7.
  9. Wellbutrin XR Summary of product characteristics. GlaxoSmithKline, June 2016.

AB: Last Updated May 2016: MLT_GIB/OTH/0001/15g