THIORIDAZINE HAS BEEN SHOWN TO PROLONG THE QTc INTERVAL IN A DOSE RELATED MANNER, AND DRUGS WITH THIS POTENTIAL, INCLUDING THIORIDAZINE, HAVE BEEN ASSOCIATED WITH TORSADE DE POINTES-TYPE ARRHYTHMIAS AND SUDDEN DEATH. DUE TO ITS POTENTIAL FOR SIGNIFICANT, POSSIBLY LIFE-THREATENING, PROARRHYTHMIC EFFECTS, THIORIDAZINE SHOULD BE RESERVED FOR USE IN THE TREATMENT OF SCHIZOPHRENIC PATIENTS WHO FAIL TO SHOW AN ACCEPTABLE RESPONSE TO ADEQUATE COURSES OF TREATMENT WITH OTHER ANTIPSYCHOTIC DRUGS, EITHER BECAUSE OF INSUFFICIENT EFFECTIVENESS OR THE INABILITY TO ACHIEVE AN EFFECTIVE DOSE DUE TO INTOLERABLE ADVERSE EFFECTS FROM THOSE DRUGS. (SEE WARNINGS, CONTRAINDICATIONS, AND INDICATIONS).
THIORIDAZINE HYDROCHLORIDE TABLETS, USP
Thioridazine hydrochloride is 2-methylmercapto-10-[2-(N-methyl-2-piperidyl) ethyl] phenothiazine.
Thioridazine is indicated for the management of schizophrenic patients who fail to respond adequately to treatment with other antipsychotic drugs. Due to the risk of significant, potentially life-threatening, proarrhythmic effects with thioridazine treatment, thioridazine should be used only in patients who have failed to respond adequately to treatment with appropriate courses of other antipsychotic drugs, either because of insufficient effectiveness or the inability to achieve an effective dose due to intolerable adverse effects from those drugs. Consequently, before initiating treatment with thioridazine, it is strongly recommended that a patient be given at least 2 trials, each with a different antipsychotic drug product, at an adequate dose, and for an adequate duration (see WARNINGS and CONTRAINDICATIONS).
However, the prescriber should be aware that thioridazine has not been systematically evaluated in controlled trials in treatment refractory schizophrenic patients and its efficacy in such patients is unknown.
Media Articles Related to Thioridazine
"Dimmer switch" drug idea could tackle schizophrenia
Source: Biology / Biochemistry News From Medical News Today [2014.08.12]
Discovery of a new mechanism of drug action could lead to the next generation of drugs to treat schizophrenia.
Could vitamin D deficiency increase the risk of schizophrenia?
Source: Mental Health News From Medical News Today [2014.07.23]
Vitamin D deficiency has been linked to numerous health problems. Now, a new study suggests that people who are vitamin D deficient may be more likely to develop schizophrenia.
Schizophrenia's genetic 'skyline' rising - suspect common variants soar from 30 to 108
Source: Schizophrenia News From Medical News Today [2014.07.23]
The largest genomic dragnet of any psychiatric disorder to date has unmasked 108 chromosomal sites harboring inherited variations in the genetic code linked to schizophrenia, 83 of which had not been...
Gene Discoveries Could Shed New Light on Schizophrenia
Source: MedicineNet Schizophrenia Specialty [2014.07.23]
Title: Gene Discoveries Could Shed New Light on Schizophrenia
Category: Health News
Created: 7/22/2014 12:35:00 PM
Last Editorial Review: 7/23/2014 12:00:00 AM
Rare gene could increase risk of schizophrenia, alcoholism and bipolar
Source: Bipolar News From Medical News Today [2014.07.22]
Scientists from the UK have identified a rare gene variant associated with developing severe chronic conditions such as schizophrenia that could lead to new treatment targets.
Published Studies Related to Thioridazine
Comparison of the effects of thioridazine and mesoridazine on the QT interval in healthy adults after single oral doses. [2007.11]
We compared the effects of single doses of thioridazine and mesoridazine on the heart rate-corrected QT (QTc) interval in healthy adult volunteers. QTc intervals and plasma concentrations of thioridazine, mesoridazine, and metabolites were measured after single oral doses of thioridazine hydrochloride 50 mg, mesoridazine besylate 50 mg, or placebo in a double-blind, crossover study...
Repeated dosing with donepezil does not affect the safety, tolerability or pharmacokinetics of single-dose thioridazine in young volunteers. [2004.11]
AIM: To investigate the effects of donepezil at steady state on the safety, tolerability and pharmacokinetics of a single dose of thioridazine, in healthy subjects... CONCLUSIONS: Repeated dosing with donepezil, 5 mg daily for 2 weeks, had no significant effect on the safety, tolerability or pharmacokinetics of thioridazine. Thioridazine was poorly tolerated.
Effect of fluoxetine and imipramine on the pharmacokinetics and tolerability of the antipsychotic quetiapine. [2002.04]
The effects of fluoxetine and imipramine on the pharmacokinetics and nonpsychiatric side effect profile of quetiapine fumarate were investigated in 26 patients with schizophrenia, schizoaffective disorder, or bipolar disorder in a multicenter, two-period, multiple-dose, open-label, randomized trial.
Psychomotor effects of zaleplon and thioridazine coadministration. [2000.06]
OBJECTIVE: To assess the potential pharmacokinetic and pharmacodynamic interaction of zaleplon and thioridazine administered concomitantly in healthy volunteers... CONCLUSION: The results of single-dose administration showed an additive pharmacodynamic interaction between zaleplon and thioridazine at 1 h in one of four tests and supra-additivity for 4 h in another test. This interaction is relatively short in duration due to the short half-life of zaleplon.
Withdrawal of haloperidol, thioridazine, and lorazepam in the nursing home: a controlled, double-blind study. [1999.08.09]
BACKGROUND: Ongoing regimens of haloperidol, thioridazine, and lorazepam are commonly administered to manage behavior problems in nursing home residents. Nevertheless, there is controversy over whether periodic drug withdrawal should be attempted when those medications are prescribed. This study addressed that issue by examining the effects of discontinuing treatment with haloperidol, thioridazine, and lorazepam among residents of a large suburban nursing home... CONCLUSIONS: Results of this work suggest that longterm use of haloperidol, thioridazine, and lorazepam in nursing homes to manage agitation should be closely monitored for their efficacy. Furthermore, routine attempts at drug withdrawal should be considered for most residents taking psychotropic medication.
Clinical Trials Related to Thioridazine
Feasibility of Thioridazine as a Mobilizing Agent for CD34+ Hematopoietic Progenitor Cells [Recruiting]
This study will investigate the possibility of using the drug thioridazine (also called
Mellaril) to increase the number of certain types of cells moving from the bone marrow to
the circulation in a group of healthy humans. The types of cells we hope to collect are
called CD34+ progenitor, or stem cells. These cells can be used in the laboratory to better
understand a number of diseases and suggest new strategies for therapy. Perhaps the most
important potential application of human stem cells is the generation of cells and tissues
that could be used for cell-based therapies, as a renewable source of replacement cells and
tissues to treat diseases including Alzheimer's diseases, spinal cord injury, stroke, burns,
heart disease, diabetes, osteoarthritis, and rheumatoid arthritis.
Study With IT-Aided Preventive Program in Schizophrenia [Not yet recruiting]
Information Technology-aided Program of Relapse Prevention in Schizophrenia (ITAREPS) will
decrease the number of hospitalizations in patients with schizophrenia or schizoaffective
disorder who are treated in the outpatient psychiatric setting, as evidenced by the reduction
of the total number of hospitalizations due to relapse of psychosis at the end of the
12-months follow-up period in the active ITAREPS group compared to the control
Changes in Heart Rhythms Associated With Antipsychotic Drug Treatment [Recruiting]
This study is being done to look at the electrical activity of the heart. This study will
help decide whether taking recordings for a 24-hour period gives more useful information
than recording it for a few seconds in a doctor's office. The study will compare 24 hour ECG
results of patients taking thioridazine (Mellaril) to those of other patients taking
different medications that took part in another study.
Reducing Antipsychotic-Induced Weight Gain in Children With Metformin [Recruiting]
Recent but limited short term studies have shown that Metformin can slow down weight gain in
obese children and in children with psychotropic-induced weight gain, two distinct pediatric
populations that are at risk for obesity related co-morbid conditions. The purpose of this
study is to conduct a long term prospective pilot cohort study to investigate the use of
Metformin to prevent or decrease weight gain in two cohorts of children: 1) children with
psychotropic induced weight gain on Metformin and 2) children with BMI above the 95th
percentile on Metformin. Both study populations will be enrolled in a lifestyle weight
Page last updated: 2014-08-12