Fluphenazine, sold under the brand names Prolixin among others, is an antipsychotic medication.[1] It is used in the treatment of chronic psychoses such as schizophrenia,[1][2] and appears to be about equal in effectiveness to low-potency antipsychotics like chlorpromazine.[3] It is given by mouth, injection into a muscle, or just under the skin.[1] There is also a long acting injectable version that may last for up to four weeks.[1] Fluphenazine decanoate, the depot injection form of fluphenazine, should not be used by people with severe depression.[4]
Common side effects include movement problems, sleepiness, depression and increased weight.[1] Serious side effects may include neuroleptic malignant syndrome, low white blood cell levels, and the potentially permanent movement disorder tardive dyskinesia.[1] In older people with psychosis as a result of dementia it may increase the risk of dying.[1] It may also increase prolactin levels which may result in milk production, enlarged breasts in males, impotence, and the absence of menstrual periods.[1] It is unclear if it is safe for use in pregnancy.[1]
Fluphenazine is a typical antipsychotic of the phenothiazine class.[1] Its mechanism of action is not entirely clear but believed to be related to its ability to block dopamine receptors.[1] In up to 40% of those on long term phenothiazines, liver function tests become mildly abnormal.[5]
Fluphenazine came into use in 1959.[6] The injectable form is on the World Health Organization’s List of Essential Medicines.[7] It is available as a generic medication.[1] It was discontinued in Australia around mid 2017.[8]
Medizinische Verwendung
A 2018 Cochrane review found that fluphenazine was an imperfect treatment and other inexpensive drugs less associated with side effects may be an equally effective choice for people with schizophrenia.[9]
Side effects
Einstellung
Das britische National Formulary empfiehlt einen schrittweisen Entzug beim Absetzen von Antipsychotika, um ein akutes Entzugssyndrom oder einen schnellen Rückfall zu vermeiden.[10] Zu den Entzugserscheinungen gehört häufig Übelkeit, Erbrechen, und Appetitlosigkeit.[11] Weitere Symptome können Unruhe sein, vermehrtes Schwitzen, und Schlafstörungen.[11] Seltener kommt es vor, dass sich die Welt dreht, Taubheit, oder Muskelschmerzen.[11] Die Symptome klingen im Allgemeinen nach kurzer Zeit ab.[11]
Es gibt vorläufige Hinweise darauf, dass das Absetzen von Antipsychotika zu einer Psychose führen kann.[12] Es kann auch zu einem erneuten Auftreten der behandelten Erkrankung kommen.[13] In seltenen Fällen kann es zu Spätdyskinesien kommen, wenn das Medikament abgesetzt wird.[11]
Pharmakologie
Pharmacodynamics
See also: Antipsychotic § Pharmacodynamics, and Antipsychotic § Comparison of medications
Fluphenazine acts primarily by blocking post-synaptic D2 receptors in the basal ganglia, cortical and limbic system. It also blocks alpha-1 adrenergic receptors, muscarinic-1 receptors, and histamine-1 receptors.[14][15]