Trifluoperazine

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Revision as of 00:10, 27 October 2020 by Helen (talk | contribs) (Side Effects)

[[Category: ]] Drug Class: Antipsychotics, typical; Antipsychotic 1st Generation

Trifluoperazine (中文:[[ ]]) is a typical antipsychotic or 1st Generation antipsychotic medication. It is used to treat

  • Schizophrenia
  • Short-term adjunctive management of severe anxiety
  • Severe nausea and vomiting

It helps patient to think more cleaerly, feel less nervous, and take part in everyday life. It can reduce aggressive behavior and the desire to hurt oneself/others. It helps to decrease hallucinations.

Pronunciation

Trifluoperazine 1mg

Drug Names

Generic Name 藥名 HA Code 藥物代碼 Classification藥物分類
Trifluoperazine Tab 1 mg TRIF01 P1S1S3
Trifluoperazine Tab 5 mg TRIF02 P1S1S3

Mechanism of Action

Trifluoperazine has central antiadrenergic, antidopaminergic, and minimal anticholinergic effects. It works by blocking postsynaptic mesolimbic dopamine D1 and D2 receptors in the brain, minimizing such symptoms of schizophrenia as hallucinations, delusions and disorganized thought and speech. Antiemetic effects are attributed to dopamine receptor blockade in the medullary chemoreceptor trigger zone. The presumed effectiveness of antipsychotic drugs relied on their ability to block dopamine receptors. This assumption arose from the dopamine hypothesis that maintains that both schizophrenia and bipolar disorder are a result of excessive dopamine activity.

Dosage

Indication Dose
Schizophrenia By mouth

ADULT:

  • 2 - 5 mg twice daily
  • Usual range 15 – 20 mg daily in divided doses
  • Up to 50 mg daily
Short-term adjunctive management

of severe anxiety

By mouth

ADULT:

  • 2 – 6 mg daily in divided doses

ELDERLY:

  • Lower initial dose to be given
  • Increased gradually according to response
Severe nausea and vomiting

By mouth

ADULT:

  • 2 – 4 mg daily in divided doses
  • Maximum 6 mg daily

Trifluoperazine is not approved for the treatment of dementia-related behavior problems. Typical (First-generation) antipsychotic agents may increase mortality in such patients. Most fatalities appeared to result from cardiovascular-related events (e.g. heart failure, sudden death) or infectious (mostly pneumonia).

Side Effects

Extrapyramidal symptoms (EPS) are frequent, especially at doses exceeding 6 mg daily. These symptoms include:

  • Drooling/trouble swallowing
  • Restlessness/constant need to move
  • Shaking (tremor)
  • Shuffling walk
  • Stiff muscles
  • Severe muscle spasms/cramping (such as twisting neck, arching back, eyes rolling up)
  • Mask-like expression of the face
  • Tardive dyskinesia (any uncontrollable movements such as lip smacking, mouth puckering, tongue thrusting, chewing, or unusual arm/leg movements

Other adverse effects of trifluoperazine include the following:

Endocrine disorders

Common: hyperprolactinaemia (elevated levels of the hormone prolactin, which for females may result in

  • Galactorrhea (unwanted breast milk)
  • amornorrhea (missed/stopped periods),

For males it may result in

  • decreased sexual ability, or
  • gynecomastia (enlarged breast)
Muscle/Nervous system disorders:

Common:

  • Sedation or drowsiness
  • Extrapyramidal symptoms (EPS)

-Tremor -Akathisia -Parkinsonism -Tardive dyskinesia

  • Anticholinergic side-effects such as:

-Dry mouth -Constipation -Blurred vision Not known:

  • Neuroleptic malignant syndrome
  • Convulsion
Metabolism disorders

Not known:

  • Hyponatraemia
  • Syndrome of inappropriate antidiuretic hormone secretion (SIADH)
Cardiac disorders

Rare:

  • Ventricular arrhythmia
  • Ventricular fibrillation, or tachycardia

Not known:

  • Electrocardiogram QT prolonged
  • Postural hypotension
Hepatic disorder Jaundice (such as yellowing eyes/skin, persistent nausea, vomiting, stomach/abdominal pain)
Skin
  • Photosensitivity reactions
  • Skin pigmentation
  • Contact dermatitis
Common: breast pain, galactorrhoea

Common:

  • weight gain

Pharmacokinetics

Oral bioavailability Sulpiride is readily absorbed after oral doses.
Onset of action Peak plasma concentrations are reached 3 – 6 hours after an oral dose.
Metabolism It is metabolized in the liver
Elimination half-life

It is excreted in the urine and faeces.

The elimination half-life is approximately 8 hours.