Incidence and onset of delayed seizures after overdoses of extended-release bupropion
Received 7 April 2008; received in revised form 29 June 2008; accepted 2 July 2008.
Abstract
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 ≥600 mg in adults and ≥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 ≤ 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 ≥ 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.
Conclusion
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.
aMaryland Poison Center/Department of Pharmacy Practice and Science, University of Maryland Baltimore, Baltimore, MD 21201
bKentucky Regional Poison Center, Kosair Children's Hospital, Louisville, KY 40202
cRegional Poison Control Center, Children's Hospital of Michigan, Detroit, MI 48201
dCentral Ohio Poison Center, Nationwide Children's Hospital, Columbus, OH 43205
eNew Mexico Poison and Drug Information Center, University of New Mexico Health Sciences Center, Albuquerque, NM 87131
Corresponding author. Maryland Poison Center, University of Maryland School of Pharmacy, Level 01, Baltimore, Maryland 21201.
ABSTRACT