CONTEXT. We report a successful acute reversal of potential life threatening QRS complex widening and prolonged QT interval following dosulepin overdose using intravenous lipid emulsion 20% in an unstable patient. CASE DETAILS. A 36-year-old female following the ingestion of 5.25 g of dosulepin. On submission the QRS complex was 120 ms and the QT interval was 348 ms (BP 129/71 mmHg, HR 113 beats/min). Her level of consciousness deteriorated and the patient had episodes of seizures. The patient received bicarbonate, 200 mmol, and assisted ventilation. Ninety minutes following submission, the QRS complex was 158 ms and the QT interval was 422 ms (BP 118/55 mmHg, HR 91 beats/min), and to treat the intoxication intravenous lipid emulsion 20% was dosed as 1.5 ml/kg (100 ml) in 5 min followed by 400 ml in 20 min. Blood pressure was immediately stabilised and the monitored QRS complex narrowed and QT interval became shorter. DISCUSSION. Cyclic antidepressants affect the cardiac conduction system and the myocardium. The exact mechanism of action from intravenous lipid emulsions may not be determined from the data presented, and the obtained effect does not rule out the supposed effects of alkalinisation and supported ventilation. However, the effects of the treatment of the severe dosulepin intoxication support the theory of intravenous lipid emulsions creating an intravenous lipid sink for drugs with high lipid solubility.

The aim of this study was to characterize the clinical signs and symptoms of exposures to aripiprazole overdoses. We retrospectively identified all aripiprazole exposures reported to the Danish Poison Information Centre (DPIC) from June 2007 to May 2015. Information concerning demographics, ingested dose and symptoms was extracted from the DPIC database and medical records. Information on death and admission to hospital was obtained from Danish national registers. We analysed 239 cases, 86 concerning single-drug exposures to aripiprazole, and 153 cases where aripiprazole had been taken with at least one other substance (mixed-drug). The median ingested aripiprazole dose was 105 mg (IQR: 50-1680 mg) in the single-drug exposure group and 120 mg (IQR: 60-225 mg) in the mixed-drug exposure group. The most commonly reported symptom was light sedation, reported in 63% of the single-drug group and 50% of the mixed-drug exposure group. There were no malignant arrhythmias or ECG abnormalities after single-drug exposures. No deaths were recorded in relation to the intake. We found a long-term mortality rate of 13 deaths per 1000 person-years (95% CI: 7; 23 per 1000 person-years), which is significantly higher than in an age- and gender-matched background population. In conclusion, we found that aripiprazole overdoses had few and mild symptoms predominantly related to the sedative properties. We detected a benign cardiovascular safety profile and no new safety concerns. Our findings may support an increased threshold of 300 mg for hospital admission after a single-drug exposure with aripiprazole and symptoms not worse than light sedation.

The number of specific antidotes available is low compared to the wide range of substances, of natural or synthetic origin, able to produce toxic symptoms in the human body. Some of these antidotes being very specific in target and effect, e.g., antagonism at the m-opioid receptors by naloxone in an opioid overdose, other antidotes being unspecific, e.g., glucagon or atropine in the case of betablocker poisoning or activated charcoal with its ability reduce absorption of a wide range of toxic substances. In the following, we present four important antidotes (N-acetylcysteine, deferoxamine, methylene blue and physostigmine) and focus on some of their reported potentially severe adverse effects.