What are the common side effects of Wellbutrin (bupropion) during the first week of treatment?

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Common Side Effects During the First Week of Wellbutrin (Bupropion)

During the first week of Wellbutrin (bupropion) treatment, the most common side effects include insomnia, anxiety, dry mouth, nausea, dizziness, headache, and constipation. 1 These initial side effects are typically most pronounced during the first few days of treatment as your body adjusts to the medication.

Most Common Initial Side Effects

  • Sleep disturbances:

    • Insomnia and difficulty staying asleep
    • Taking the medication earlier in the day can help minimize this effect
  • Neurological effects:

    • Anxiety and feeling jittery
    • Dizziness
    • Headaches
  • Gastrointestinal effects:

    • Dry mouth
    • Nausea
    • Constipation

Timeline and Management

Most side effects are most noticeable during the first 1-2 weeks and tend to diminish as your body adjusts to the medication 2. The FDA-approved labeling notes that if you experience troublesome side effects:

  • Do not abruptly stop taking the medication without consulting your healthcare provider
  • Most side effects are mild to moderate in intensity
  • Taking the medication with food may help reduce nausea
  • Staying hydrated can help with dry mouth and constipation

Important Precautions During First Week

  1. Seizure risk: While rare, seizures are a serious potential side effect, especially during dose initiation. Risk factors include:

    • History of head trauma or seizures
    • Excessive alcohol use
    • Abrupt discontinuation of alcohol or sedatives 3
  2. Blood pressure monitoring: Bupropion can cause increases in blood pressure, particularly during the initial treatment period 3

  3. Neuropsychiatric symptoms: Monitor for increased anxiety, agitation, or changes in mood, especially in the first few days 3

What to Avoid During First Week

  • Alcohol: Limit or avoid alcohol during treatment with bupropion, especially during the first week, as it may increase seizure risk 1

  • Driving/operating machinery: Until you know how bupropion affects you, use caution with activities requiring alertness 1

  • Other medications: Do not start new medications without consulting your healthcare provider, as bupropion has several drug interactions 1

When to Contact Your Healthcare Provider

Contact your healthcare provider immediately if you experience:

  • Seizures
  • Severe headache or dizziness
  • Significant increase in blood pressure
  • Severe allergic reactions
  • Thoughts of suicide or significant mood changes

Dosing Considerations

Starting at a lower dose and gradually increasing helps minimize initial side effects:

  • Typical starting dose is 150 mg once daily for 3-7 days
  • After the initial period, dose may be increased to 300 mg daily if needed and tolerated 1, 2

Remember that while these side effects can be uncomfortable, they are generally temporary and often improve after the first week of treatment. If side effects are severe or persistent, consult your healthcare provider about possible dose adjustments or alternative treatments.

References

Research

15 years of clinical experience with bupropion HCl: from bupropion to bupropion SR to bupropion XL.

Primary care companion to the Journal of clinical psychiatry, 2005

Guideline

Medication Management with Bupropion XL

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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