One-year experience with aripiprazole exposures

Extrapyramidal Syndrome due to Aripiprazole Overdose in a Young Woman: An Unusual Case Report

Aripiprazole is an atypical antipsychotic medication indicated for the treatment of schizophrenia and bipolar disorders. The drug has been shown to exhibit acceptable efficacy and is often preferred as a first-line psychiatric treatment option owing to its lower incidence of adverse effects. While first-generation antipsychotics are associated with extrapyramidal syndrome (EPS), atypical antipsychotics such as aripiprazole are generally associated with a lower frequency of EPS. In this case, we present a 31-year-old woman with a history of bipolar disorder who developed EPS after ingesting 200 mg of aripiprazole. Fortunately, her symptoms improved with the administration of biperiden, and she was discharged five days after ingestion. This case highlights the potential for significant consequences associated with aripiprazole, even within its therapeutic index.

Prolonged QRS Widening After Aripiprazole Overdose

BACKGROUND

Aripiprazole is an atypical antipsychotic with a long half-life. Overdose can result in protracted somnolence and cardiac disturbances, particularly QT interval prolongation.

METHODS

This is a single case report of a 14-year-old boy who took an overdose of aripiprazole and developed QRS widening.

CASE

A 14-year-old boy intentionally ingested 20 tablets of aripiprazole (5 mg). He was brought to the emergency department when his ingestion was discovered. The patient's vital signs were as follows: temperature, 37.7°C; heart rate, 108 beats/min; blood pressure, 138/98 mm Hg; and respirations, 16 breaths/min. Activated charcoal was administered within 90 minutes of ingestion. Initial electrocardiogram (EKG) showed sinus tachycardia, with a QRS of 138 ms and QT interval of 444 ms. QRS duration was 90 ms on an EKG performed 3 months earlier. A bolus of sodium bicarbonate was administered, and the patient was transferred to the pediatric intensive care unit. Repeat EKG demonstrated a QRS of 156 ms, and a sodium bicarbonate infusion was initiated. The patient continued to have QRS prolongation for the next 8 days, reaching a peak of 172 ms 3 days postingestion. Despite aggressive treatment with sodium bicarbonate, there was persistent QRS prolongation; however, the patient did not have any dysrhythmias and remained hemodynamically stable. The patient was discharged 9 days postingestion when the QRS duration normalized to 82 ms. Genetic testing revealed that the patient was a CYP2D6 poor metabolizer.

CONCLUSIONS

This case suggests that aripiprazole toxicity may possibly be associated with QRS prolongation without associated dysrhythmias or cardiovascular compromise. In addition, toxicity may be prolonged in patients who are CYP2D6 poor metabolizers.

Torsades De Pointes after Administration of Low-Dose Aripiprazole

OBJECTIVE:

To describe a case of torsades de pointes (TdP) in a patient treated with aripiprazole.

CASE SUMMARY:

A 42-year-old white male with schizophrenia, diabetes, hypertension, and a history of stroke was admitted to the intensive care unit following 2 days of fever, diarrhea, and altered mental status. Following the resolution of his acute illness, previous therapy with quetiapine 400 mg orally at bedtime was resumed for schizophrenia and presumed delirium. Quetiapine was discontinued after 1 dose because of QTc interval prolongation. Twenty-three days later, with a baseline Q Tc interval of 414 milliseconds, aripiprazole 2.5 mg orally once daily was initiated. Following 5 days of aripiprazole therapy, the patient had a cardiac arrest due to TdP. Normal sinus rhythm was restored after 30 seconds of cardiopulmonary resuscitation, 1 shock of 200 Joules, and 4 g of intravenous magnesium sulfate. Serial electrocardiographs obtained after aripiprazole discontinuation revealed resolution of QTc interval prolongation.

DISCUSSION:

Aripiprazole is a second-generation antipsychotic that may be selected for patients with prolonged QTc intervals and at risk for TdP. Data from trials indicate that aripiprazole has minimal effects on the QTc interval. However, in this case, aripiprazole was associated with TdP in a patient with minimal risk factors. The Naranjo probability scale was used to determine a probable association between aripiprazole and the development of TdP. To our knowledge, this is the first reported case of TdP associated with the use of aripiprazole.

CONCLUSIONS:

Five days of low-dose aripiprazole therapy was associated with the development of TdP in a man with minimal risk factors. Clinicians should be aware of this potential adverse drug event with aripiprazole.

Toxicology and overdose of atypical antipsychotics

BACKGROUND

Second-generation antipsychotic medications, or "atypical antipsychotics," are now first-line therapy in the treatment of schizophrenia and other psychotic disorders, and are additionally being used in a wide array of other psychiatric and non-psychiatric conditions in both adults and children. Overdose is frequently reported to poison control centers.

OBJECTIVES

We review the toxicology and general management of poisonings involving the atypical antipsychotic medications.

DISCUSSION

The most serious toxicity involves the cardiovascular system and the central nervous system. All typical and atypical antipsychotics cause sedation, which is pronounced in overdose. The most common cardiovascular effects that occur after atypical antipsychotic overdose are tachycardia, mild hypotension, and prolongation of the QTc interval. Other clinical syndromes in overdose include neuroleptic malignant syndrome (NMS) and antimuscarinic delirium. Seizures may be observed. No antidotes exist for these poisonings, but they most often do well with supportive care.

CONCLUSION

Antipsychotic overdose produces a gamut of manifestations that affect multiple organ systems. Treatment is primarily supportive. Specific therapies for NMS, hypotension, and seizures are discussed.

Risk assessment of isolated aripiprazole exposures and toxicities: a retrospective study

STUDY OBJECTIVE

To characterize the clinical effects of acute isolated aripiprazole poisonings and to assess the toxic dose of this drug.

METHODS

All isolated acute aripiprazole exposures reported to a poison control system from January 2002 through September 2006 were retrospectively reviewed. Patients with incomplete information or those lost to follow-up were excluded.

RESULTS

A total of 286 cases were identified. Mean age was 18.9 years (SD 15.7), with a range of 6 months-70 years. Seventy-seven patients (27%) were <or=6 years, 80 patients (28%) were 7-17 years, and 129 patients (45%) were >or=18 years. Doses were known in 255 patients (89%). Symptoms occurred in 158 patients (55%): somnolence 89 (56%), tachycardia 32 (20%, heart rate 102-186), nausea/vomiting 29 (18%), dystonic reactions 21 (13%), tremor 9 (6%), agitation 3 (2%), dizziness 3 (2%), paresthesia 2 (1%), headache 2 (1%), dysphagia 1 (<1%), syncope 1 (<1%), minor facial swelling 1 (<1%), and hypotension 1 (<1%). None of the patients required intubation, and there were no deaths or EKG abnormalities. Median dose for symptomatic and asymptomatic groups were 25 and 15 mg, respectively, for <or=6 years (p = 0.02); 60 and 30 mg for 7-17 years (p = 0.01); and 100 and 75 mg for >or=18 (p = 0.25). In comparison of drug groups (Group 1, <or=20 mg; Group 2, 21-90 mg; Group 3, >or=91 mg), symptoms were more likely to occur in Group 2 versus Group 1 (OR 2.29, 95% CI 0.79-6.61) in patients <or=6 years; in Group 3 versus Group 1 (OR 3.39, 95% CI 1.07-10.73) followed by Group 2 versus Group 1 (OR 1.14, 95% CI 0.36-3.56) in patients 7-17 years; and in Group 3 versus Group 1 (OR 1.36, 95% CI 0.54-3.42) but not any more likely in Group 2 versus Group 1 (OR 0.92, 95% CI 0.33-2.52) in patients >or=18 years.

CONCLUSIONS

Acute aripiprazole poisonings most commonly result in sedation, sinus tachycardia, nausea/vomiting, or dystonic reactions. Symptoms are more likely with doses above 90 mg, although pediatric patients can be affected at a lower dose.

A systematic review of cardiovascular effects after atypical antipsychotic medication overdose

As the use of atypical antipsychotic medications (AAPMs) increases, the number of overdoses continues to grow. Cardiovascular toxicity was common with older psychiatric medications but seems uncommon with AAPM. We conducted a systematic literature review to describe the cardiovascular effects reported after overdose of 5 common AAPM: aripiprazole, olanzapine, quetiapine, risperidone, and ziprasidone. We included case reports and case series describing overdose of these 5 medications identified in a search of MEDLINE, EMBASE, and abstracts from major toxicology meetings. We found 13 pediatric cases (age, <7 years), 22 adolescent cases (age, 7-16 years), and 185 adult cases. No pediatric case described a ventricular dysrhythmia or a cardiovascular death. In the adolescent and adult cases, we found numerous reports of prolonged corrected QT interval and hypotension, but there were only 3 cases of ventricular dysrhythmia and 3 deaths that may have been due to direct cardiovascular toxicity. The results from case series reports were similar to the single case report data. Our review suggests that overdose of AAPM is unlikely to cause significant cardiovascular toxicity.