Stupor drugs overdose

III. Clinical presentation. Overdose with any of these drugs may cause drowsiness, ataxia, nystagmus, stupor, coma, and respiratory arrest. Deep coma may result in absent reflexes, fixed pupils, and depressed or absent electroencephalo-graphic (EEG) activity. Hypothermia is common. Most agents also slow gastric motility and decrease muscle tone. Hypotension with a large overdose is caused primarily by depression of cardiac contractility and, to a lesser extent, loss of venous tone. 

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