Serotonin Syndrome from 5-Hydroxytryptophan Supplement Ingestion in a 9-Month-Old Labrador Retriever.

INTRODUCTION: 5-Hydroxytryptophan (5-HTP) supplements are available over the counter and labeled as sleeping aids and anxiolytics for human use. 5-HTP is a serotonin precursor and overdose can lead to serotonin syndrome. CASE REPORT: A 9-month-old female Labrador retriever was evaluated after ingestion of a 5-HTP supplement. Signs of agitation developed within 1 h of ingestion, and emesis was attempted by the owner with  3% hydrogen peroxide (H2O2) orally. On presentation, the dog was obtunded, bilaterally mydriatic and salivating. Physical exam revealed tachypnea, tachycardia, hyperthermia, and hypertension. Eighteen hours post presentation, the dog developed melena, hematemesis, and pigmenturia. A hemogram revealed mild anemia with evidence of oxidative erythrocyte damage (eccentrocytes, Heinz bodies, and siderocytes). A chemistry panel revealed markedly elevated creatine kinase and hyperbilirubinemia, supporting hemolytic anemia. A urinalysis revealed pigmenturia. Hemolytic anemia was presumed to be caused by oxidative damage secondary to gastrointestinal ulceration and circulatory embolism of H2O2. Treatment included fluid therapy, a mannitol constant rate infusion, antiemetics, gastroprotectants, and cyproheptadine as a serotonin antagonist. The patient responded well to treatment and was discharged within 48 h of presentation. DISCUSSION: Serotonin syndrome is an increasingly common toxic syndrome in veterinary medicine with the availability of over-the-counter medications that alter serotonin metabolism. The importance of appropriate client education regarding emesis with H2O2 is highlighted.

Creatin-kinase elevation after accidental ingestion of almotriptan in an 18-month-old girl.

Few studies have been published to demonstrate tolerability and efficacy of almotriptan in adolescents and children with migraine, particularly in the first years of life, though preliminary results are favorable. We report the case of an 18-month-old infant with elevation of serum levels of creatin-kinase after the accidental ingestion of almotriptan. A previously healthy 18-month-old girl (weight: 13 kg) was admitted to our Department four hours after the accidental ingestion of 6.25 mg of almotriptan (0.48 mg/kg), without any specific symptom. The performed investigations showed high serum levels of creatin-kinase (CK) (527 IU/L; normal values: 24-170 IU/L). Transaminase, creatinine, aldolase, myoglobin and troponin T serum levels were normal. The electrocardiogram proved negative. Initial management consisted of parenteral rehydration with saline solution. CK levels lowered significantly at 12 hours (455 IU/L) and at 65 hours (188 IU/L) after the ingestion. No symptoms were observed before discharge and on follow-up.

Acute chlorophenylpiperazine overdose: a case report and review of the literature.

This case report describes an acute overdose in a female patient with the serotonin mixed agonist-antagonist m-chlorophenylpiperazine (mCPP), a new synthetic drug that is also a metabolite of the antidepressant trazodone. Following ingestion of three multi-coloured tablets, she developed anxiety, agitation, drowsiness, flushing, visual disturbances and tachycardia. The mCPP concentration was 320 ng/mL in plasma and 2300 ng/mL in urine. Amphetamine (40 ng/mL), benzoylecgonine (47 ng/mL) and alcohol (0.7 g/L) were also detected in plasma. The concentration of mCPP in plasma was approximately six times higher than the usual concentration measured in patients under trazodone treatment (26-108 ng/mL, average 56 ng/mL). However, one should be careful to link the observed symptoms to the use of mCPP only as the other drugs that have also been taken or an interaction between the drugs could also have played a role.

Rapid high-performance liquid chromatographic measurement of buspirone in human plasma after overdose.

For toxicological purposes, a rapid reversed-phase high-performance liquid chromatographic method was developed for the determination of the anxiolytic drug, buspirone, in human plasma. A liquid-liquid procedure was used to extract this compound from plasma in the presence of an internal standard, quinupramine. The analysis was performed on a Spherisorb S5 C8 analytical column with UV detection at 240 nm. No endogenous compounds were found to interfere. A linear response was observed over the concentration range 5-100 ng/mL. A good accuracy (bias < or =7.9%) was achieved for all quality controls, with intra-day and inter-day variation coefficients equal or less than 7.6%. The limit of quantification was 5 ng/mL. Stability of buspirone in plasma stored at different temperatures was checked. This rapid method (run time <12 min) was used to manage an acute poisoning involving buspirone.