Carbamazepine overdose*
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Carbamalepine overdose· Cardiac arrhytbmJas and conduction delay: ftrst report After ingesting an unknown quantity of carbamazepine,a 27-yeJIr-old man was found staggering and ataxic with slurred speech. He became hyper-reflexic, lethargic, then comatose and had hypoactive bowel sounds. ECG showed a sinus rhythm of 150/ min. The peJlk carbamazepine blood level was 38.4I1g/ ml and the epoxide metabolite was very high (compared with a therapeutic situation) at Illig/ ml at 6 hours. An 18-month-Old girl who could have ingested up to 6 x 200mg tablets had a grand mal seizure 4 hours later. and was comatose on arrival. She was hyper-refleltic and had decreased bowel sounds . 18-24 hours later she was conscious, and appeared well. Her blood level was 2JlIg/ml on admission and 7IJgI ml at 18 hours. A oomatose woman was found having taken an unknown overdose of carbamazepine + amitriptyline. She had dilated pupils reacting sluggishly to light, and was hypOrefiexic with bypoactive rowel sounds. ECG showed a sinus tachycardia of 10Q, with prolonged PR, QRS and OT intervals. Coma deepened, but 24 hours later she was much improved, though tachycardia persisted, and nystagmus was present. Bowel sounds were active, but over the next hours slle lapsed baCk into coma, with grand mal seizures and continued sinus tachycardia. At 48 hours she could open her eyes and later recovered completely. A 17-year-old man look carbamazepine, acetazolamide and flurazepam. He was ataxic, with slurred speech, then 4 hours later became comatose with sinus tachycardia of liD/min. He improved over 36 hours. Plasma caroomazepine levels at 2 hours and 13 hours were Il.7j.1g/ml and 351-l8/ml, respectively. All patients were given supportive measures. intubation and ventilatory assistance. gastric lavage, activated charcoal, and physostigmine when required. The spectrum of symptoms included seizures, myoclonus, coma (cyclic in one). respiratory depression, abnormal tendon reflexes, nystagmus, sinus tachycardia, ataxia, delayed gastric emptying (and delayed absorption as in the last patient) and prolonged A V conduction. DysrhYlhmias and conduction defects have been seen with lricylic toxicity, but have not previously been described with carbamazepine {which is structurally related to imipraminel . The highest blood level was found in the first patient with the mildest symptoms . Sullivan,l.B. eI al ., Neurology 31, 621 (MIlY 1980/ 4 Reactions 12 Jun 1981 0157-7271/81/0612-0004/0$00. 50/0 © ADISPress
Transcript of Carbamazepine overdose*
Carbamalepine overdose·
Cardiac arrhytbmJas and conduction delay: ftrst report After ingesting an unknown quantity of carbamazepine,a 27-yeJIr-old man was found staggering and ataxic with slurred speech. He became hyper-reflexic, lethargic, then comatose and had hypoactive bowel sounds. ECG showed a sinus rhythm of 150/ min. The peJlk carbamazepine blood level was 38.4I1g/ ml and the epoxide metabolite was very high (compared with a therapeutic situation) at Illig/ ml at 6 hours. An 18-month-Old girl who could have ingested up to 6 x 200mg tablets had a grand mal seizure 4 hours later. and was comatose on arrival . She was hyper-refleltic and had decreased bowel sounds. 18-24 hours later she was conscious, and appeared well. Her blood level was 2JlIg/ml on admission and 7IJgI ml at 18 hours. A oomatose woman was found having taken an unknown overdose of carbamazepine + amitriptyline. She had dilated pupils reacting sluggishly to light, and was hypOrefiexic with bypoactive rowel sounds. ECG showed a sinus tachycardia of 10Q, with prolonged PR, QRS and OT intervals. Coma deepened, but 24 hours later she was much improved, though tachycardia persisted, and nystagmus was present. Bowel sounds were active, but over the next hours slle lapsed baCk into coma, with grand mal seizures and continued sinus tachycardia. At 48 hours she could open her eyes and later recovered completely. A 17-year-old man look carbamazepine, acetazolamide and flurazepam. He was ataxic, with slurred speech, then 4 hours later became comatose with sinus tachycardia of liD/min. He improved over 36 hours. Plasma caroomazepine levels at 2 hours and 13 hours were Il.7j.1g/ml and 351-l8/ml, respectively. All patients were given supportive measures. intubation and ventilatory assistance. gastric lavage, activated charcoal, and physostigmine when required. The spectrum of symptoms included seizures, myoclonus, coma (cyclic in one). respiratory depression, abnormal tendon reflexes, nystagmus, sinus tachycardia, ataxia, delayed gastric emptying (and delayed absorption as in the last patient) and prolonged A V conduction. DysrhYlhmias and conduction defects have been seen with lricylic toxicity, but have not previously been described with carbamazepine {which is structurally related to imipraminel. The highest blood level was found in the first patient with the mildest symptoms. Sullivan,l.B. eI al., Neurology 31, 621 (MIlY 1980/
4 Reactions 12 Jun 1981 0157-7271/81/0612-0004/0$00.50/0 © ADISPress
