Trifluoperazine Other names: Trifluoperazine hydrochloride

Phenothiazines increase the risk of ventricular arrhythmias when given with drugs which prolong the Q-T interval; drugs causing electrolyte imbalances.

Trifluoperazine may diminish the effect of oral anticoagulants.

Antacids can reduce the absorption of phenothiazines.

Potentiation may occur if antipsychotic drugs are combined with CNS depressants such as alcohol, hypnotics, anaesthetics and strong analgesics, or with antihypertensives or other drugs with hypotensive activity, anticholinergics or antidepressants. Phenothiazines may antagonise the action of guanethidine.

Desferrioxamine should not be used in combination with trifluoperazine oral solution, since prolonged unconsciousness has occurred after combination with the related prochlorperazine.

Serum levels of phenothiazine can be reduced to non-therapeutic concentrations by concurrent administration of lithium. Dosage increases may be needed.

Severe extrapyramidal side-effects or neurotoxicity have been observed in patients concurrently treated with lithium and trifluoperazine. Sleep walking has been described in some patients taking phenothiazines and lithium.

An approximately 3-fold increased risk of cerebrovascular adverse events have been seen in randomised placebo controlled clinical trials in the dementia population with some atypical antipsychotics. The mechanism for this increased risk is not known. Trifluoperazine should be used with caution in patients with risk factors for stroke.

Trifluoperazine may aggravate Parkinsonism and antagonise the action of levodopa.

Although trifluoperazine has minimal anticholinergic activity, this should be borne in mind when treating patients with narrow angle glaucoma.

In patients with Parkinson’s disease, symptoms may be worsened, and the effects of levodopa reversed.

Patients with cardiovascular disease including arrhythmias should also be treated with caution. Because trifluoperazine may increase activity, care should be taken in patients with angina pectoris. Caution should be used in patients with cardiovascular disease or family history of QT prolongation.

Since phenothiazines may lower the convulsive threshold, patients with epilepsy should be treated with caution, and metrizamide avoided.

Phenothiazines should be used with care in extremes of temperature since they may affect body temperature control.

Trifluoperazine has been available since 1958. There are some animal studies that indicate a teratogenic effect, but results are conflicting. There is no clinical evidence (including follow-up surveys in over 800 women who had taken low-dosage Trifluoperazine oral solution during pregnancy) to indicate that trifluoperazine has a teratogenic effect in man. Nevertheless, drug treatment should be avoided in pregnancy unless essential, especially during the first trimester.

Neonates exposed to antipsychotics (including trifluoperazine) during the third trimester of pregnancy are at risk of adverse reactions including extrapyramidal and/or withdrawal symptoms that may vary in severity and duration following delivery. There have been reports of agitation, hypertonia, hypotonia, tremor, somnolence, respiratory distress, or feeding disorder. Consequently, newborns should be monitored carefully.

Trifluoperazine crosses the placenta and passes into the milk of lactating dogs; breast feeding should only be allowed at the discretion of the physician.

Trifluoperazine may cause side effects including drowsiness, dizziness and visual disturbances which interfere with the ability to drive and operate machinery.

Do not drive or use machines when you first start to take this medicine until you are certain that you are not getting these side effects.

Lassitude, drowsiness, dizziness, transient restlessness, insomnia, dry mouth, blurred vision, muscular weakness, anorexia, mild postural hypotension, skin reactions including photosensitivity reactions, weight gain, oedema and confusion may occasionally occur. Tachycardia, constipation, urinary hesitancy and retention, and hyperpyrexia have been reported very rarely. Adverse reactions tend to be dose related and to disappear.

Hyperprolactinaemia may occur at higher dosages with associated effects such as galactorrhoea, amenorrhoea or gynaecomastia; certain hormone-dependent breast neoplasms may be affected.

Phenothiazines can produce ECG changes with prolongation of the QT interval and T-wave changes; ventricular arrhythmias (VF, VT (rare)), sudden unexplained death; cardiac arrest and Torsades de pointes have been reported. Such effects are rare with trifluoperazine. In some patients, especially non-psychotic patients, trifluoperazine even at low dosage may cause unpleasant symptoms of being dulled or, paradoxically, of being agitated.

Extrapyramidal symptoms are rare at daily oral dosages of 6 mg or less; they are considerably more common at higher dosage levels. These symptoms include parkinsonism; akathisia, with motor restlessness and difficulty in sitting still; and acute dystonia or dyskinesia, which may occur early in treatment and may present with torticollis, facial grimacing, trismus, tongue protrusion and abnormal eye movements including oculogyric crises. These effects are likely to be particularly severe in children. Such reactions may often be controlled by reducing the dosage or by stopping medication. In more severe dystonic reactions, an anticholinergic antiparkinsonism drug should be given.

Tardive dyskinesia of the facial muscles, sometimes with involuntary movements of the extremities, has occurred in some patients on long-term high dosage and, more rarely, low dosage phenothiazine therapy, including trifluoperazine. Symptoms may appear for the first time either during or after a course of treatment; they may become worse when treatment is stopped. The symptoms may persist for many months or even years, and while they gradually disappear in some patients, they appear to be permanent in others. Patients have most commonly been elderly, female, or with organic brain damage. Particular caution should be observed in treating such patients.

Periodic gradual reduction of dosage to reveal persisting dyskinesia has been suggested, so that treatment may be stopped if necessary.

Anticholinergic antiparkinsonism agents may aggravate the condition. Since the occurrence of tardive dyskinesia may be related to length of treatment and total cumulative dosage, trifluoperazine should be given for as short a time and at as low a dosage as possible.

The neuroleptic malignant syndrome is a rare but occasionally fatal complication of treatment with various neuroleptic drugs, and is characterised by hyperpyrexia, muscle rigidity, altered consciousness and autonomic instability.

Intensive symptomatic treatment, following discontinuation of trifluoperazine should include cooling. Intravenous dantrolene has been suggested for muscle rigidity.

Mild cholestatic jaundice, and blood dyscrasias such as agranulocytosis, pancytopenia, leucopenia and thrombocytopenia have been reported very rarely.

Signs of persistent infection should be investigated.

Very rare cases of skin pigmentation and lenticular opacities have been reported with trifluoperazine.

Cases of venous thromboembolism, including cases of pulmonary embolism and cases of deep vein thrombosis have been reported with antipsychotic drugs- Frequency unknown.

Pregnancy, puerperium and perinatal conditions – Drug withdrawal syndrome neonatal – Frequency not known.