thioridazine (Mellaril is a discontinued brand)

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GENERIC NAME: thioridazine


DRUG CLASS AND MECHANISM: Thioridazine is an oral antipsychotic medication used for the management of schizophrenia. Thioridazine is one of the older, first-generation antipsychotic medications. Examples of other first-generation antipsychotics include:

Although the exact mechanism of antipsychotics is unknown, scientists believe that they may work by blocking the action of dopamine in the brain. Dopamine is a neurotransmitter (chemical) that nerves use to communicate with one another. Thioridazine is used when patients do not respond to other antipsychotics.

PRESCRIBED FOR: Thioridazine is used for the management of schizophrenia and depressive disorders.


Long-term use of thioridazine may lead to a potentially irreversible condition called tardive dyskinesia (involuntary movements of the jaw, lips, and tongue).

A potentially fatal complex referred to as neuroleptic malignant syndrome has been reported with anti-psychotic drugs, including thioridazine. Patients who develop this syndrome may have

Tardive dyskinesia and neuroleptic malignant syndrome can result from thioridazine treatment. These side effects can be severe, and require medical help. Neuroleptic malignant syndrome is a medical emergency.

Other serious side effects and adverse reactions include

  • Elderly patients with dementia-related psychosis treated with antipsychotics are at an increased risk of death, and thioridazine should not be used for treating patients with dementia-related psychosis.
  • Thioridazine may impair the mental and physical abilities required for driving a car or operating machinery.
  • Life threatening abnormal heartbeats (arrhythmias) may occur.
  • Thioridazine may cause low blood pressure.
  • A decrease in blood cell counts has been reported during treatment with thioridazine. Low white blood cell counts may increase the risk for infections.
  • Thioridazine may increase blood levels of prolactin, a hormone.
  • Thioridazine may increase the risk of seizures.
Medically Reviewed by a Doctor on 11/6/2015

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