Fluphenazine: Effects, Uses & Risks

Fluphenazine is an active ingredient that has been used successfully as a neuroleptic in human medicine since the 1960s due to its properties. Fluphenazine is indicated for psychotic syndromes with delusions and hallucinations, diagnosed schizophrenia, and psychomotor agitation states, among other conditions.

What is fluphenazine?

The medical drug fluphenazine was approved in the Federal Republic of Germany for the treatment of diseases as early as 1961. Under the trade names Omca and Lyogen, the substance was prescribed in tablet form and used to treat various mental and psychiatric disorders, respectively. Due to its properties, the white solid is assigned to the active substance class of neuroleptics and forms part of the group of so-called phenothiazines. Fluphenazine has a moral mass of 437.52 g/mol. In chemistry and pharmacology, the drug is described by the molecular formula C 22 – H 26 – F 3 – N 3 – O – S. Even today, it is taken exclusively orally in tablet form. In addition to the well-known trade names, fluphenazine is also commercially available as a generic drug.

Pharmacological action

Fluphenazine is an active ingredient of the phenothiazine group. As such, it is considered a neuroleptic and has antipsychotic and sedative properties. Fluphenazine belongs to the so-called highly potent neuroleptics, which also include the related drugs haloperidol and perphenazine. These form the most neuroleptically potent group of first-generation neuroleptics. The pharmacological action of fluphenazine makes the drug a dopamine antagonist. It binds competitively to the dopamine receptors (D2 receptors) in the human brain, thereby inhibiting the binding of the neurotransmitter dopamine. A mild sedative, antipsychotic and drive-reducing effect occurs. In addition to its effect on dopamine receptors, fluphenazine is also active at serotonin receptors (5HT2 receptors). Here, too, binding of the neurotransmitter serotonin is prevented, leading to an enhancement of the sedative, antipsychotic, and drive-reducing effects.

Medical application and use

Because fluphenazine, unlike other neuroleptics such as triflupromazine, elicits only neuroleptic or sedative effects, the drug is used in human medicine exclusively in psychiatry. In veterinary medicine, however, fluphenazine is also used as a sedative to induce anesthesia. The neuroleptic is taken orally by patients as a film-coated tablet after prior prescription by a physician. It is sold exclusively through pharmacies, as the drug is subject to prescription and pharmacy requirements in Europe and the United States. At present, the drug is used exclusively in mono-preparations. Medicines containing fluphenazine as the active ingredient are indicated when patients have been diagnosed with schizophrenia. In these cases, fluphenazine may be prescribed to provide relapse prophylaxis or to treat chronic psychosis. However, fluphenazine is also prescribed for thought disorders, acute delusions, hallucinations, and ego disorders. Its use can be short- or long-term, depending on the treatment goal, with the latter being the rule.

Risks and side effects

Before taking fluphenazine for the first time, it is important to check whether there is an intolerance (allergy) to the active substance. If this is the case, treatment should not be given. Such a contraindication is also given if patients suffer from severe kidney or liver dysfunction. In addition, the use of neuroleptics can enhance the effects of analgesics and anesthetics. Consequently, before surgery, the dose of the preparations to be used should be reduced accordingly. Since fluphenazine also intensifies the effects of alcohol, nothing should be drunk shortly before or after taking the active substance. Because fluphenazine is a neuroleptic, undesirable side effects may occur after taking it. However, this does not necessarily have to be the case. Nevertheless, some patients report disturbances of the extrapyramidal motor system (EPMS). These are usually expressed by tremor (involuntary, rhythmic contraction of various muscle groups) or rigor (pathogenically increased tension of the skeletal muscles).Due to the intake of fluphenazine, blood pressure values below 100/60 mmHg (hypotension) may also occur. It is also possible that treatment with fluphenazine leads to a long-term excess of the age-typical heart rate (tachycardia). In some clinical trials, treated individuals also reported gastrointestinal symptoms of vomiting, nausea, general malaise, and constipation (constipation). Other side effects reported to date also include dry mouth and headache.