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Updated: Jul 17, 2026

A Computerized Test Battery to Study Pharmacodynamic Effects on the Central Nervous System of Cholinergic Drugs in Early Phase Drug Development
Published on: February 11, 2019
[Sympathomimetic syndrome caused by autointoxication with methylphenidate]
L F D van Vulpen1, M M Malingré, R Lange
1Afd. Interne Geneeskunde, Meander Medisch Centrum, Postbus 1502, 3800 BM Amersfoort.
Abstract:
A 31-year-old man claimed that he had ingested more than 100 tablets of methylphenidate (10 mg), 20 tablets ofibuprofen (400 mg) and 2 bottles of wine. At admission, signs of sympathomimetic syndrome were observed, including agitation, hallucinations, mydriasis and sinus tachycardia. The patient was treated with activated charcoal and an oral laxative. Given the possibly lethal dose of methylphenidate, the patient was admitted to the intensive care unit for observation. He made a full recovery and was discharged 36 hours after admission. Toxicological analysis indicated a plasma-ethanol concentration of 0.27% and a maximum serum-methylphenidate concentration of 176 microg/l (therapeutic range: 5-40 microg/l). The active metabolite ethylphenidate was also present at toxic concentrations. Treatment of potentially lethal methylphenidate poisoning includes prevention of absorption, careful observation and support of vital functions as necessary.
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