Novel psychotropic medications in children: new toxicities to master

Comparative cardiovascular safety of risperidone and olanzapine, based on electrocardiographic parameters and blood pressure: a prospective open label observational study

Objective:

To assess the cardiovascular safety of two commonly prescribed atypical antipsychotics risperidone (RSP) and olanzapine (OZP) in schizophrenic patients, using electrocardiography (ECG) and Blood Pressure (BP).

Materials and Methods:

This was a 10-week prospective open label, observational study, carried out in a newly diagnosed 64 schizophrenic patients receiving either RSP or OZP. RSP (n = 32) was started with dose of 2 mg/day and increased to 4 mg/day after 2 weeks, whereas OZP (n = 32) was started at a dose of 5 mg/day and was increased to 10 mg/day after 2 weeks. Heart rate (HR), ECG parameters (PR, RR, QRS, QT intervals and QTc and QTd) and BP (systolic and diastolic in supine and standing position) were recorded at baseline (before drug therapy)) and during follow-up visits at 2(I), 6(II) and 10(III) weeks.

Results:

In the RSP group, at II and III follow-ups, a significant increase in the HR (P = 0.018, P = 0.011 respectively) as well as in QTc (P = 0.025, P = 0.015, respectively) was observed when compared to the basal values. In the OZP group, diastolic BP was significantly decreased in standing position at II and III follow-ups (P = 0.045 and P = 0.024, respectively) compared to the basal values. When the two groups were compared with each other, no significant differences were observed in the changes of HR, PR, QRS, QT, RR, QT, QTd and SBP (supine and standing position); and DBP (supine position). However, DBP in standing position showed a significant decrease in the OZP group at II and III follow-up (P = 0.036 and P = 0.016, respectively) compared to the RSP group.

Conclusions:

Patients treated with OZP are at higher risk to develop postural hypotension as compared with RSP; hence RSP could be better tolerated by patients taking antihypertensive drugs as compared with OZP whereas OZP would have a safer cardiac profile.

Overdoses and ingestions of second-generation antipsychotics in children and adolescents

OBJECTIVE

We reviewed the available published data on intentional or unintentional secondgeneration antipsychotic overdoses in children and adolescents. The prescribing of secondgeneration antipsychotics has continued to increase over the past decade for children, adolescents, and adults. The authors reviewed the existing literature to determine the circumstances, presenting problems, treatment, and outcomes of youths who were exposed to nontherapeutic doses of these medications.

METHODS

A systematic English-language Medline search of all reports (1989-2005) and a review of the bibliographies of all articles obtained was done to identify papers reporting an overdose or ingestion of a second-generation antipsychotic. Data were reviewed on clozapine, risperidone, olanzapine, ziprasidone, quetiapine, and aripiprazole. The annual reports of the American Association of Poison Control Centers National Data Collection System were reviewed from 1990 to 2003, the most recent report currently available. All fatalities in children and youths under 18 years of age were included.

RESULTS

The literature review identified 40 reports that included 63 patients, ranging in age from 1 day to 17 years of age. The clinical presentations included drowsiness, lethargy, agitation, irritability, combativeness, and tachycardia. There were 11 fatalities in the cases reviewed, 1 from clozapine overdose, 3 from risperidone overdose, 2 from olanzapine overdose, and 5 from quetiapine overdose. All other cases reported no significant sequelae and resolved without any reported clinical consequences. Duration of overdose symptoms ranged from 24 hours to 7 days. One case of clozapine intoxication showed resolution of symptoms in 6 hours and, in another case of olanzapine overdose, symptoms resolved in 13 days. The most frequently employed treatments included intubation, gastric lavage, activated charcoal, intravenous fluids, artificial respiration, and restraints or sedatives.

CONCLUSIONS

There is a need for future case reports to include serum medication level, weight of patient, coingestants, the health of the patient at baseline, relevant laboratory and toxicology studies and a standardized scale to rate the level of consciousness, such as the Glasgow Coma Scale. The existing pharmacovigilance data reports indicate these medications are relatively safe when taken in overdose, particularly when coingestants are not involved.

Toxicology and overdose of atypical antipsychotic medications in children: does newer necessarily mean safer?

PURPOSE OF REVIEW

Atypical antipsychotic medications (second-generation antipsychotics) have been increasingly used in the treatment of a number of psychotic disorders since their introduction in 1988, with the newest medication introduced in 2002. Justification for their use includes claims of equal or improved antipsychotic activity over first-generation antipsychotics, increased tolerability, and decreased side effects. However, there are still significant adverse effects and toxicities with this class of medications. Toxicologic exposures and fatalities associated with atypical antipsychotics continue to increase in the United States, with 32,422 exposures and 72 deaths in 2003. There have also been Food and Drug Administration warnings in the past year about how some atypical antipsychotics have been marketed to minimize the potentially fatal risks and claiming superior safety to other atypical antipsychotics without adequate substantiation, indicating the toxicologic potential of these agents may be underestimated.

RECENT FINDINGS

Continued research to evaluate adverse effects and tolerability of atypical antipsychotics compared with first-generation antipsychotics and each other is reviewed. This article also reviews the pharmacodynamics, pharmacokinetics, and drug interactions with these medications. New therapeutic monitoring recommendations for this class of medications have also been proposed. Finally, clinical toxicity in overdose and management are reviewed.

SUMMARY

While new atypical antipsychotic medications may have a safer therapeutic and overdose profile than first-generation antipsychotic medications, many adverse and toxic effects still need to be considered in therapeutic monitoring and overdose management.

Effects of psychotropic medications on the pediatric electrocardiogram and recommendations for monitoring

Reports of sudden unexpected death in pediatric patients taking selected psychotropic drugs have raised the possibility of ventricular dysrhythmias as the cause of these deaths. The use of psychotropic drugs in the pediatric population has increased significantly in recent years with increasing reports of electrocardiogram abnormalities, particularly prolongation of the corrected QT interval. Many factors affect the susceptibility of the heart to conduction abnormalities and sudden ventricular dysrhythmias in pediatric patients taking psychotropic drugs. These complex relations include genetic predisposition, structural cardiac disease, drug-drug interactions, drug dosage, and drug metabolism and clearance. Many specific psychotropic drugs have been reported to prolong the QTc interval and increase the risk of ventricular dysrhythmias and sudden death. This article discusses the various factors that may influence the electrocardiogram in pediatric patients taking psychotropic drugs and recommendations for monitoring these patients.