What to do if a patient develops hives after starting Wellbutrin (bupropion)?

Management of Hives After Starting Wellbutrin (Bupropion)

Discontinue bupropion immediately and do not rechallenge the patient due to risk of progression to more severe hypersensitivity reactions. 1

Immediate Management

1. Stop bupropion immediately

   • Bupropion can cause severe allergic reactions including urticaria (hives), angioedema, and in rare cases, progression to Stevens-Johnson syndrome or anaphylactic shock 1
   • Hives are a clear sign of hypersensitivity reaction that requires medication discontinuation

2. Administer antihistamines

   • Provide second-generation H1 antihistamine (preferred over first-generation):
     • Cetirizine 10 mg orally or IV 2
     • Loratadine 10 mg orally 2
   • Avoid first-generation antihistamines like diphenhydramine due to sedation and potential to convert minor reactions to more severe ones 2

3. Monitor for progression to more severe reaction

   • Observe patient for at least 15 minutes 2
   • Watch for signs of:
     • Angioedema (swelling of face, lips, tongue)
     • Respiratory symptoms (difficulty breathing, stridor)
     • Hypotension
     • Gastrointestinal symptoms (vomiting, abdominal pain)

Assessment for Severe Reaction

If the patient shows any of these concerning signs:

• Mild reaction (hives only): Continue monitoring, provide antihistamines
• Moderate reaction (hives plus cough, shortness of breath, tachycardia): Administer IV corticosteroids (hydrocortisone 200 mg IV) 2
• Severe/anaphylactic reaction (hypotension, angioedema, respiratory distress): Administer epinephrine 0.3 mg IM into anterolateral thigh, call emergency services 2

Follow-up Care

1. Medication documentation

   • Document bupropion allergy clearly in the patient's medical record
   • Advise patient to avoid all formulations of bupropion (Wellbutrin, Zyban, Aplenzin, etc.) 1

2. Alternative antidepressant selection

   • Choose an antidepressant from a different class (SSRI, SNRI, etc.)
   • Venlafaxine has been successfully used in patients with bupropion-induced hypersensitivity reactions 3

3. Patient education

   • Explain that rechallenge is contraindicated due to risk of more severe reaction
   • Inform that delayed hypersensitivity reactions to bupropion can occur up to 4 weeks after initiation 3, 4
   • Advise to seek immediate medical attention if symptoms worsen

Important Considerations

• Bupropion-induced hypersensitivity reactions can be delayed, appearing 2-4 weeks after starting the medication 3, 4

• Risk factors for bupropion-induced hypersensitivity include:

  • Male gender
  • Age 17-40 years
  • History of allergic reactions 3

• While some case reports suggest successful rechallenge with a different formulation (SR vs XL) 4, this approach is not recommended due to the risk of more severe reactions including erythema multiforme and anaphylaxis 1, 5

Pitfalls to Avoid

• Do not rechallenge with bupropion in any formulation despite case reports of successful rechallenge, as severe reactions including erythema multiforme can occur 5
• Do not delay discontinuation of bupropion once hypersensitivity is identified, as continued exposure can lead to progression of symptoms 6
• Do not use first-generation antihistamines like diphenhydramine as they may worsen outcomes 2
• Do not assume mild presentation will remain mild - monitor closely as reactions can progress rapidly 1