Thioridazine

QTC Prolongation; Elderly with Dementia Related Psychosis

QTc Prolongation

  • QTc Prolongation is dose related. Torsades de pointes type arrhythmias and sudden death.
  • Reserved for use only in refractory schizophrenia failed to show an acceptable response to adequate course of other antipsychotics.

Increased Mortality in Elderly Patients with Dementia Related Psychosis

  • Elderly patients with dementia related psychosis treated with atypical antipsychotic drugs are at an increased risk of death compared to placebo.
  • Analyses of seventeen placebo controlled trials (modal duration of 10 weeks, largely in patients taking atypical antipyschotic drugs, revealed a risk of death in the drug treated patients of between 1.6 to 1.7 times that seen in placebo treated patients. Over the course of a typical 10-week controlled trial, the rate of death in drug treated patients was about 4.5% compared to a rate of about 2.6% in the placebo group.
  • Although the causes of death were varied, most of the deaths appeared to be either cardiovascular (e.g., heart failure, sudden death) or infectious (e.g., pneumonia) in nature.
  • Observational studies suggest that, similar to atypical antipsychotic drugs, treatment with conventional antipsychotic drugs may increase mortality.
  • The extent to which the findings of increased mortality in observational studies may be attributed to the antipsychotic drug as opposed to some characteristic(s) of the patients is not clear.
  • This drug is not approved for the treatment of patients with dementia-related psychosis (See WARNINGS in package insert).

Monitoring data

  • Baseline and periodic ECG and serum potassium during therapy
  • If baseline QTc > 450 msec do not initiate therapy
  • If QTc > 500 msec during therapy, discontinue therapy
  • Contraindicated for use with Cytochrome P450 2D6 inhibitors and agents known to prolong QTc interval
  • Contraindicated for use in patients with history of cardiac arrhythmias or congenital long QT syndrome