Wellbutrin SR (Bupropion SR) Safety in Post-CABG Patients
Wellbutrin SR can be used safely in patients with a history of CABG, but requires blood pressure monitoring due to the risk of hypertension. The FDA label specifically notes that bupropion was studied in patients with stable congestive heart failure without major safety concerns, though it cautions about lack of controlled trials in patients with recent myocardial infarction or unstable cardiac disease 1.
Key Safety Considerations
Cardiovascular Safety Profile
The evidence strongly supports bupropion's cardiovascular safety in cardiac patients:
In a study of 36 depressed inpatients with preexisting heart disease (left ventricular impairment, ventricular arrhythmias, and/or conduction disease), bupropion did not cause significant conduction complications, did not exacerbate ventricular arrhythmias, had low rates of orthostatic hypotension, and had no effect on pulse rate 2. However, treatment was discontinued in 14% due to adverse effects, including exacerbation of baseline hypertension in 2 patients.
Bupropion does not cause the cardiac conduction delays or orthostatic hypotension seen with tricyclic antidepressants 3. It showed no adverse effects on heart rate, blood pressure, or cardiac conduction in multiple studies.
Blood Pressure Monitoring is Essential
The primary cardiovascular concern with bupropion in post-CABG patients is hypertension, not cardiac conduction or ischemia. The FDA label explicitly states: "Treatment with bupropion hydrochloride extended-release tablets (SR) can result in elevated blood pressure and hypertension. Assess blood pressure before initiating treatment... and monitor periodically during treatment" 1.
- Bupropion caused a rise in supine blood pressure in cardiac patients 2
- Two patients in the cardiac disease study had treatment discontinued due to exacerbation of baseline hypertension 2
Evidence in Smoking Cessation Post-Cardiac Events
Two major studies examined bupropion specifically in cardiovascular disease patients for smoking cessation:
In 629 CVD patients, bupropion SR showed no clinically significant changes in blood pressure or heart rate, with similar discontinuation rates to placebo (5.4% vs 6.0%) 4
In 248 smokers hospitalized with acute cardiovascular disease (primarily MI and unstable angina), bupropion groups showed no difference in cardiovascular mortality at 1 year (0% vs 2% placebo) or cardiovascular events 5
Clinical Algorithm for Use
Step 1: Assess Current Cardiovascular Status
- Ensure patient is stable post-CABG (not in acute/unstable phase)
- Check baseline blood pressure
- Review for uncontrolled hypertension
Step 2: Screen for Contraindications
- History of seizures (absolute contraindication per FDA label 1)
- Current MAOI use (14-day washout required 1)
- Uncontrolled hypertension requiring optimization first
Step 3: Initiate with Monitoring
- Start at 150 mg once daily for 3 days, then increase to 150 mg twice daily 1
- Monitor blood pressure at baseline, 1-2 weeks, and periodically thereafter
- Maximum dose 400 mg/day (200 mg twice daily) with at least 8 hours between doses 1
Step 4: Discontinue if:
- Blood pressure becomes uncontrolled or significantly elevated
- New cardiac symptoms develop (though evidence suggests this is unlikely)
Important Caveats
- The FDA label notes lack of controlled trials in patients with recent MI or unstable cardiac disease 1, but your patient has a history of CABG (not acute/recent MI), making this less relevant
- The 2011 ACC/AHA CABG guidelines emphasize beta-blockers, statins, aspirin, and ACE inhibitors as core post-CABG medications 6, but do not address antidepressant safety
- Bupropion's mechanism does not interfere with antiplatelet therapy (aspirin, clopidogrel) that post-CABG patients require 6
In summary: Wellbutrin SR is appropriate for post-CABG patients who need antidepressant therapy or smoking cessation support, provided blood pressure is monitored and the patient is in a stable phase of recovery.