Psychoses
Adult: Initially, 20-60 mg wkly, increased up to 250 mg once a wk in severe or resistant conditions.
Indications and Dosage
Oral
Psychoses Adult: Initially, 20-60 mg wkly, increased up to 250 mg once a wk in severe or resistant conditions.
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Contraindications
Preexisting CNS depression or coma.
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Special Precautions
Pregnancy and lactation; elderly; epilepsy; preexisting cardiac conduction problems; hypokalaemia, hypomagnesemia; hypothyroidism.
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Adverse Reactions
Lower threshold for seizures, blurring of vision, dry mouth, retention of urine, constipation, orthostatic hypotension, weight gain, impaired glucose tolerance, allergic skin rashes, cholestatic jaundice; extrapyramidal effects; delirium; agitation, anxiety, depression, euphoria; anorexia, constipation, diarrhoea; alopecia; amenorrhoea, hypoglycaemia; hyponatraemia; hypersalivation, nausea, vomiting; bronchospasm; reported increased risk of breast cancer.
Potentially Fatal: Blood dyscrasias; neuroleptic malignant syndrome; alteration of heart conduction leading to QT prolongation and life threatening arrhythmias. |
Overdosage
Symptoms: deep sleep, dystonia, extrapyramidal symptoms. Treatment: supportive and symptom specific.
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Drug Interactions
Orthostatic hypotension with MAOIs; may increase sedation with alcohol, hypnotics, antihistamines, opiates; antacids containing aluminum salts may decrease absorption; additive antimuscarinic effects with TCAs; may reduce bromocriptine's ability to reduce serum prolactin; amphetamines may increase psychosis; may inihibit antiparkinsonian effects of levodopa; may increase risk of extrapyrimidal symptoms with metoclopramide; may increase phenytoin levels (phenytoin may reduce penfluridol levels); possible additive effects on QT interval with type 1a antiarrhythmics, TCAs, some quinolone antibiotics (e.g. moxifloxacin), may have additive hypotensive effects with trazodone; may increase levels of valproic acid.
Potentially Fatal: May produce neurotoxicity with lithium. |
Food Interaction
Avoid valerian, St John's wort, kava kava, gotu kola; increased risk of CNS depression.
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Action
Description:
Mechanism of Action: Penfluridol blocks the postsynaptic dopamine receptor in the mesolimbic dopaminergic system and inhibits the release of hypothalamic and hypophyseal hormones. Duration: 1 wk. Pharmacokinetics: Absorption: Absorbed from the GI tract (oral); peak plasma concentrations after 2 hr. Metabolism: Undergoes enterohepatic recycling. Excretion: Urine and faeces (as N-dealkylated metabolite). Elimination half-life: 36 hr (initial), 120 hr (terminal). |
MIMS Class
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