Serotonin syndrome following sibutramine poisoning in a child, with sequential quantification of sibutramine and its primary and secondary amine metabolites in plasma.
OBJECTIVE
To report a case of serotonin syndrome (SS) after sibutramine overdose in a child.


METHODS
A 4-year-old girl was admitted 25 h after accidentally ingesting approximately 27 pills of sibutramine (15 mg, approximately 23 mg/kg). The child developed clinical features suggestive of SS, including diaphoresis, tachycardia, hypertension, agitation, insomnia, incoordination, hypertonia (lower limbs >> upper limbs), and hallucinations. Serum creatine phosphokinase levels reached a peak on day 3 (2,577 U/L, reference value <145), suggesting mild rhabdomyolysis. No relevant changes were detected in other laboratory examinations or in the electrocardiogram throughout the period of hospitalization. The quantification of sibutramine and the active metabolites, M1 (mono-desmethyl sibutramine) and M2 (di-desmethyl sibutramine), by liquid chromatography/electrospray ionization tandem mass spectrometry in six sequential samples collected from 25 to 147 h post-ingestion revealed a nonlinear decrease in the log-scale plasma concentrations. Treatment was only supportive and involved prolonged sedation to control the agitation, sleeplessness, and hypertension; no cyproheptadine was used. The patient was discharged on day 6 and follow-up revealed no sequelae.


CONCLUSIONS
To our knowledge, this is the first report of SS after sibutramine overdose in a child, with sequential monitoring of the plasma levels of the drug and its two active metabolites. The growing consumption of weight reducing pills may increase the risk of unintentional acute toxic exposures in children.
Bucaretchi
Fábio
F
Faculty of Medical Sciences, State University of Campinas, Pediatrics and Poison Control Center, Centro de Controle de Intoxicações, Hospital das Clínicas, Universidade Estadual de Campinas, Campinas, Brazil. bucaret@fcm.unicamp.br
de Capitani
Eduardo Mello
EM
Mello
Sueli Moreira
SM
Lanaro
Rafael
R
Barros
Roberta F
RF
Fernandes
Luciane C R
LC
da Costa
José Luiz
JL
Hyslop
Stephen
S
D000931:Antidotes / Q000008:administration & dosage; D001067:Appetite Depressants / Q000032:analysis / Q000506:poisoning*; D002675:Child, Preschool; D002697:Chloral Hydrate / Q000008:administration & dosage; D002851:Chromatography, High Pressure Liquid; D003402:Creatine Kinase / Q000097:blood; D003503:Cyclobutanes / Q000097:blood / Q000506:poisoning*; D003975:Diazepam / Q000008:administration & dosage; D062787:Drug Overdose / Q000628:therapy; D005260:Female; D006801:Humans; D008874:Midazolam / Q000008:administration & dosage; D020230:Serotonin Syndrome / Q000139:chemically induced* / Q000503:physiopathology / Q000628:therapy; D021241:Spectrometry, Mass, Electrospray Ionization
D000931:Antidotes; D001067:Appetite Depressants; D003503:Cyclobutanes; D002697:Chloral Hydrate; D003402:Creatine Kinase; D003975:Diazepam; D008874:Midazolam; C058254:sibutramine