Bupropion and Seizure Risk: Bulimia-Specific vs. General Vomiting
Bupropion is absolutely contraindicated in patients with bulimia nervosa or anorexia nervosa due to a markedly elevated seizure risk, but this contraindication is specific to eating disorders—not to vomiting from other causes. 1
The Bulimia-Specific Seizure Risk
The contraindication for bupropion in bulimia is based on compelling evidence:
A landmark multicenter trial demonstrated a seizure incidence of 7.3% (4 out of 55 patients) in bulimic patients treated with bupropion—a rate far exceeding the typical 0.1% (1/1000) seizure risk seen in general populations. 2 This dramatic increase led to the explicit recommendation that bupropion should not be administered to bulimic patients. 2
The FDA drug label explicitly lists bulimia nervosa and anorexia nervosa as contraindications, specifically because these conditions predispose patients to seizures when taking bupropion. 1 This is not merely a precaution—it is an absolute contraindication. 1
Multiple obesity management guidelines consistently identify "history of seizures or any condition that predisposes to seizure such as anorexia/bulimia nervosa" as contraindications to bupropion-containing medications like naltrexone-bupropion ER. 3
Why Bulimia Increases Seizure Risk
The mechanism relates to electrolyte disturbances and metabolic derangements:
Bulimia nervosa causes electrolyte abnormalities (particularly hypokalemia and hypomagnesemia) from purging behaviors, which lower the seizure threshold independent of bupropion. 2
Abrupt discontinuation of alcohol, benzodiazepines, barbiturates, or antiepileptic drugs—behaviors sometimes seen in eating disorder populations—also predispose to seizures and represent additional contraindications to bupropion. 3
The combination of bupropion's inherent seizure risk (related to dose-dependent effects on neuronal excitability) with the metabolic instability of eating disorders creates a dangerous synergy. 4, 2
Vomiting from Other Causes: Not a Contraindication
Isolated vomiting from non-eating disorder causes (such as gastroenteritis, chemotherapy, or other medical conditions) does not contraindicate bupropion use:
Nausea and vomiting are actually common side effects of bupropion itself, occurring in 2-4% of patients in depression trials and listed as frequent adverse events in obesity medication guidelines. 3, 1, 5
The FDA label and clinical guidelines do not list vomiting or nausea as contraindications—only eating disorders specifically. 1
Antiemetic guidelines for chemotherapy-induced nausea/vomiting make no mention of avoiding bupropion, suggesting that transient vomiting from other causes is not considered a seizure risk factor. 3
Critical Clinical Distinctions
Screen specifically for eating disorder history before prescribing bupropion:
Ask directly about binge eating, purging behaviors, laxative abuse, and restrictive eating patterns—not just about current vomiting episodes. 3
A history of bulimia or anorexia nervosa remains a contraindication even if the patient is currently in remission, as the metabolic vulnerability may persist. 1
One case report documented severe bupropion abuse (3,000-4,500 mg/day) in a bulimic patient seeking appetite suppression, ultimately resulting in grand mal seizures—highlighting the particular danger in this population. 6
Other Seizure Risk Factors to Assess
Beyond eating disorders, avoid bupropion in patients with:
Prior history of seizures, structural brain lesions (stroke, tumor, trauma), or conditions lowering seizure threshold. 4, 1
Alcohol abuse or abrupt discontinuation of alcohol, benzodiazepines, barbiturates, or antiepileptic drugs. 3, 4
Doses exceeding 450 mg/day of immediate-release or 400 mg/day of sustained-release formulations, as seizure risk is dose-dependent. 4, 1, 5
Monitoring Recommendations
If bupropion is prescribed (in appropriate patients without contraindications):