Incidence and onset of delayed seizures after overdoses of extended-release bupropion.
BACKGROUND
Delayed seizures have been reported with overdoses of bupropion extended-release (XL). This study systematically evaluates the frequency and timing of seizures and an association between other toxic effects (ie, agitation, tremors, and hallucinations) and seizures.


METHODS
A 3-year multi-poison center observational study of hospitalized patients with ingestion of bupropion XL >or=600 mg in adults and >or=4 mg/kg in children was performed. Patients with coingestants or a medical history that could affect seizure occurrence were excluded. Data collection forms captured onset time of seizure(s), other symptoms, and treatment.


RESULTS
One hundred seventeen patients met inclusion criteria: median age of 22 years (range, 1.3-65 years) with 16 children <or= 3 years. Seizures occurred in 37 (31.6%) patients, with initial seizure at 0.5 to 24 hours after ingestion; 12 (32%) patients had initial seizure at > 8 hours. Subsequent seizures occurred in 49%. Children ages 1.3, 3, and 7 years, developed seizures. In patients >or= 13 years of age, median dose with seizures was 4350 mg (range, 600-54 000) compared to 2400 mg (range, 600-9000) in patients without seizures. Agitation, tremors, and hallucinations occurred in 29.7%, 40.5%, and 18.9% of patients with seizures, respectively, compared with 12.5 %, 17.5%, and 10% in patients without seizures. The neurologic effects agitation (P = .045) and tremors (P = .005) occurred more frequently.


CONCLUSIONS
Delayed seizure onset suggests a minimum observation period of 24 hours after bupropion XL overdose. Although patients experiencing agitation or tremors may be at greater risk, seizures can occur without preceding central nervous system toxicity.
Maryland Poison Center/Department of Pharmacy Practice and Science, University of Maryland Baltimore, Baltimore, MD 21201, USA. pstarr@rx.umaryland.edu
Paul
P
Starr
Wendy
W
Klein-Schwartz
Henry
H
Spiller
Perri
P
Kern
Susan E
SE
Ekleberry
Susan
S
Kunkel
D000293:Adolescent; D000328:Adult; D000368:Aged; D016642:Bupropion / Q000506:poisoning*; D016009:Chi-Square Distribution; D002648:Child; D002675:Child, Preschool; D018765:Dopamine Uptake Inhibitors / Q000506:poisoning*; D062787:Drug Overdose / Q000453:epidemiology*; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D008875:Middle Aged; D019370:Observation; D011446:Prospective Studies; D012189:Retrospective Studies; D012307:Risk Factors; D012640:Seizures / Q000139:chemically induced*; D018709:Statistics, Nonparametric
D018765:Dopamine Uptake Inhibitors; D016642:Bupropion