Characterization of gabapentin overdose using a poison center case series.
BACKGROUND
Gabapentin is an anticonvulsant that is being used for an increasing number of off-label indications. The purpose of this study is to document the clinical manifestations and outcomes of gabapentin exposures reported to poison centers.


METHODS
A multicenter prospective observational study of all gabapentin exposures reported to three poisoncenters was conducted between 4/1/98 and 4/1/2000. Cases involving gabapentin only were evaluated.


RESULTS
There were 20 cases with gabapentin as the sole substance in doses ranging from 50 mg to 35 g. Ten of the 20 cases involved children and adolescents. Clinical effects developed early and resolved within 10 hours in most patients. Seven cases were managed in the home with only observation. Four of these patients remained asymptomatic. Effects reported in the three symptomatic patients were drowsiness (3) and ataxia (1). Thirteen patients were managed in a health care facility. Nine were symptomatic with reported effects of drowsiness (6), dizziness (3), nausea/vomiting (2), tachycardia (2), and hypotension (2). None of the patients were admitted for medical care.


CONCLUSIONS
In this cases series, gabapentin exposures caused no or minimal toxicity.
Klein-Schwartz
Wendy
W
Maryland Poison Center, Department of Pharmacy Practice and Science, University of Maryland School of Pharmacy, Baltimore, Maryland 21201, USA. wkleinsc@rx.umaryland.edu
Shepherd
J Greene
JG
Gorman
Susan
S
Dahl
Brad
B
D000085:Acetates / Q000506:poisoning*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000588:Amines; D000927:Anticonvulsants / Q000506:poisoning*; D002648:Child; D002675:Child, Preschool; D003509:Cyclohexanecarboxylic Acids; D004305:Dose-Response Relationship, Drug; D062787:Drug Overdose; D005260:Female; D000077206:Gabapentin; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D011039:Poison Control Centers; D011446:Prospective Studies; D016896:Treatment Outcome; D005680:gamma-Aminobutyric Acid
D000085:Acetates; D000588:Amines; D000927:Anticonvulsants; D003509:Cyclohexanecarboxylic Acids; D005680:gamma-Aminobutyric Acid; D000077206:Gabapentin