Recommended Timing for Wellbutrin SR 100mg Twice Daily
Wellbutrin SR 100mg should be taken twice daily, with the first dose in the morning and the second dose in the early afternoon, with at least 8 hours between doses to minimize the risk of insomnia. 1
Optimal Dosing Schedule
- Morning dose: Take the first 100mg tablet in the morning with or without food
- Afternoon dose: Take the second 100mg tablet in the early afternoon (no later than mid-afternoon)
- Spacing: Maintain at least 8 hours between doses
- Avoid evening dosing: The second dose should not be taken late in the day to minimize the risk of insomnia 2, 1
Rationale for This Schedule
Bupropion SR (sustained-release) has specific pharmacokinetic properties that inform its optimal dosing schedule:
- The SR formulation has a time to maximum concentration (Tmax) of approximately 3 hours 3
- The half-life of bupropion is approximately 21 hours, with its primary active metabolite (hydroxybupropion) having a similar half-life of about 20 hours 3
- Taking the medication twice daily ensures more consistent blood levels throughout the day 4
- Evening administration increases the risk of insomnia, which is one of the most common side effects 1, 5
Important Considerations
Insomnia Prevention
Bupropion can cause significant insomnia. Taking the second dose too late in the day substantially increases this risk 2, 1. The recommendation to avoid late-day dosing is consistent across multiple guidelines.
Consistency
Taking Wellbutrin SR at approximately the same times each day helps maintain steady blood levels, which is important for both efficacy and minimizing side effects 3.
Food Interactions
Bupropion SR can be taken with or without food, as food does not significantly affect its absorption 3.
Common Pitfalls to Avoid
- Taking doses too close together: This may increase the risk of side effects and potentially seizures
- Taking the second dose in the evening: This significantly increases the risk of insomnia 2, 1
- Inconsistent timing: Variable dosing times can lead to fluctuating blood levels and potentially reduced efficacy
- Missing doses: If a dose is missed, take it as soon as remembered, but if it's close to the next scheduled dose, skip the missed dose and return to the regular schedule (never double up)
Bupropion SR's twice-daily dosing schedule is designed to optimize therapeutic effects while minimizing adverse effects, particularly insomnia. The morning and early afternoon schedule provides the best balance between maintaining therapeutic blood levels and avoiding sleep disturbances.