decanoate and fluphenazine enanthate are very slowly absorbed from the
site of subcutaneous or intramuscular injection. They both gradually
release fluphenazine into the body and are therefore suitable for use as
The plasma half-life of fluphenazine after a single dose was 14.7 hours in 1 patient given the hydrochloride by mouth and 14.9 and 15.3 hours in 2 patients given the hydrochloride by intramuscular injection. (1) The half-life was 3.6 and 3.7 days in 2 patients given the enanthate intramuscularly and 9.6 and 6.8 days in 2 patients given the decanoate intramuscularly. Peak plasma-fluphenazine concentrations occurred earlier in patients given fluphenazine decanoate compared with those who received the enanthate. Fluphenazine sulphoxide and 7-hydroxyfluphenazine were identified in the urine and faeces.
SCHIZOPHRENIA AND OTHER PSYCHOSES, MANIA: Initially 2.5-10mg daily in 2-3 div doses. Adjusted to 20mg/day according to response.
25mg IM every 2-4 weeks
In psychotics, this drug produces calmness and reduction of aggressive hehaviour. Initiative is reduced but intellectual capability is not. Halllucinations and delusions disappear and patients become responsive. Seizure threshold is reduced while serum prolactin is increased.
depression, extra-pyramidal reactions.
Aluminium Salts: Decrease efficacy. Antacids should be given 1 hour before or 2 hours after chlorpromazine
ANticholinergics: decrease efficacy and increase the anticholinergic side effects of chlorpromazine.
Barbiturates: Decreases efficacy.
Barbiturate anaesthetics: Increase frequency and severtiy of neuromuscular excitation and hypotension.
Bromocriptine: Efficacy decreased by chlorpromazine.
Charcoal: Prevents absorption of chlorpromazine.
Epinephrine, Norepinephrine: Pressor effect decreased, peripheral vasoconstrictive effect antagonised.
Lithium: Diorientation, unconsciousness and extra-pyramidal symptoms.
Meperidine: Excessive sedation and hypotension
TCAs: Serum concentration increased by chlorpromazine
Valproic acid: Efficacy potentiated.
Propranolol: Increased plasma levels of both drugs.
MAOIs: Additive orthostatic hypotensive effect.
Lab Tests: Pregnancy test: False positive rsults.
Plasma boud iodine(PBI): Increase in PBI occurs.
Effect & Precaution
Insomnia, dry mouth, nausea, epigastric distress, seizures, hypotension, tachycardia.
Precaution: Epilepsy, intestinal obstruction, cardiovascular disease, pheochromocytoma, cerebral damage.
Pregnancy: Use with caution.
Breast Feeding: Use with caution.
Man: May be given in reduced dose