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Thorazine Side Effects

Generic name: chlorpromazine

Medically reviewed by Drugs.com. Last updated on Dec 22, 2023.

Note: This document provides detailed information about Thorazine Side Effects associated with chlorpromazine. Some dosage forms listed on this page may not apply specifically to the brand name Thorazine.

Applies to chlorpromazine: oral tablets, parenteral injection.

Important warnings This medicine can cause some serious health issues

    Increased Mortality in Geriatric Patients with Dementia-related Psychosis
  • Geriatric patients with dementia-related psychosis treated with antipsychotic agents are at an increased risk of death.101 105 106 n

  • Analyses of 17 placebo-controlled trials in geriatric patients mainly receiving atypical antipsychotic agents revealed an approximate 1.6- to 1.7-fold increase in mortality compared with that in patients receiving placebo.101 105 106 n

  • Most fatalities appeared to result from cardiovascular-related events (e.g., heart failure, sudden death) or infections (mostly pneumonia).105 106 n

  • Observational studies suggest that conventional or first-generation antipsychotic agents also may increase mortality in such patients.101 105 106

  • Antipsychotic agents, including chlorpromazine, are not approved for the treatment of dementia-related psychosis.101 105 106 n

Side effects include:

Extrapyramidal reactions (e.g., Parkinson-like symptoms, dystonia, akathisia, tardive dyskinesia), drowsiness, dizziness, skin reactions or rash, dry mouth, orthostatic hypotension, amenorrhea, galactorrhea, weight gain.

For healthcare professionals

Applies to chlorpromazine: compounding powder, injectable solution, oral capsule extended release, oral concentrate, oral syrup, oral tablet, rectal suppository.

General adverse events

The most frequently reported side effects included drowsiness, sedation, dry mouth, and nasal stuffiness.[Ref]

Hematologic

Nervous system

Acute dystonia and/or dyskinesia typically were transitory, occurring more frequently in children and young adults within the first 4 days of treatment or after dose changes.

Akathisia usually occurred after patients were given large initial doses.

Autonomic dysfunction occurred as a symptom of neuroleptic malignant syndrome.

Convulsive seizures have occurred more frequently in patients with a history of seizures and/or with EEG abnormalities.

Momentary fainting occurred most commonly in patients after the first injection, with a lower frequency of occurrence in subsequent injections; patients given oral formulations rarely fainted after the initial dose.

Parkinsonism more commonly occurred in adults and elderly patients after weeks to months of treatment.

Sedation and somnolence occurred more frequently at the start of treatment.[Ref]

Gastrointestinal

Psychiatric

Altered consciousness occurred as a symptom of neuroleptic malignant syndrome.[Ref]

Ocular

Accommodation disorder was related to anticholinergic effects of this drug.

Eye deposits occurred in the anterior segment of the eye from drug accumulation; however, the deposits usually did not have impact on sight.[Ref]

Genitourinary

Lactation and breast engorgement in female patients occurred with large doses.

Urinary retention was linked to anticholinergic effects of this drug.[Ref]

Dermatologic

Metabolic

Cardiovascular

Cardiac arrest may be related to dose as well as preexisting conditions (e.g., cardiac disease, old age, hypokalemia, concurrent tricyclic antidepressants).

Hypertensive crisis occurred after abrupt withdrawal of treatment.

Orthostatic hypotension occurred more frequently in elderly and/or volume depleted patients, and was more likely to occur with IM administration.

Sudden cardiac death may be related to causes of cardiac origin.[Ref]

Endocrine

Other

Hyperthermia occurred as a symptom of neuroleptic malignant syndrome.

Mild fevers have occurred in patient who received large doses intramuscularly.

Sudden death may be related to causes of cardiac origin, asphyxia, convulsions, or hyperpyrexia.[Ref]

Respiratory

Local

Contact sensitization has occurred in individuals who frequently handled this drug.[Ref]

Immunologic

Hepatic

Musculoskeletal

Elevated creatine phosphokinase, muscular rigidity, and myoglobinuria/rhabdomyolysis are symptoms of neuroleptic malignant syndrome.

Rigidity occurred as a symptom of neuroleptic malignant syndrome.[Ref]

Renal

Hypersensitivity

References

1. (2002) "Product Information. Thorazine (chlorpromazine)." SmithKline Beecham

2. Cerner Multum, Inc. "UK Summary of Product Characteristics."

3. Cerner Multum, Inc. "Australian Product Information."

Frequently asked questions

Further information

Thorazine side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.