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Ventricular fibrillation coinciding with phentermine initiation.
Patrick Tobbia1, Leslie A Norris, Lawrence D Klima
1Department of Internal Medicine, Cone Health, Greensboro, North Carolina, USA. tobbia@gmail.com
BMJ Case Reports
|October 19, 2012
Summary
Phentermine, a weight-loss drug, can trigger dangerous ventricular fibrillation by causing coronary artery vasospasm. Discontinuing phentermine resolved the patient's symptoms, highlighting the importance of monitoring cardiac function during treatment.
Area of Science:
- Cardiology
- Pharmacology
- Internal Medicine
Background:
- Phentermine is a commonly prescribed stimulant medication for weight loss.
- Adverse cardiovascular events, though rare, are a potential concern with stimulant therapy.
- Ventricular fibrillation is a life-threatening cardiac arrhythmia requiring immediate intervention.
Observation:
- A 70-year-old female patient initiated phentermine therapy.
- The patient developed recurrent ventricular fibrillation shortly after starting phentermine.
- Cardiac catheterization revealed right coronary artery vasospasm.
Findings:
- The right coronary artery vasospasm was successfully treated with intravenous nitroglycerin.
- Discontinuation of phentermine led to the resolution of the patient's ventricular fibrillation and symptoms.
- The patient remained symptom-free following phentermine cessation.
Implications:
- This case suggests a potential link between phentermine and coronary artery vasospasm leading to ventricular fibrillation.
- Clinicians should exercise caution and consider cardiac monitoring in patients prescribed phentermine, especially those with cardiovascular risk factors.
- Further research is warranted to elucidate the mechanisms and prevalence of phentermine-induced vasospasm and arrhythmias.
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