The active ingredient perphenazine is a highly potent neuroleptic. It is used to treat delusions, hallucinations, and psychosis.
What is perphenazine?
Perphenazine is a member of the phenothiazine group of drugs. The active ingredient was developed in the 1950s. It reached the market in 1957 and was sold in Germany as a monopreparation under the trade name Decentan. In modern times, perphenazine is used less frequently because more modern neuroleptics are now available.
Pharmacologic action
Perphenazine exerts its effects primarily in psychoses. In most cases, these are caused by disturbances in the metabolism of the brain. These disturbances are thought to be responsible for increased excitability in various brain areas. These active centers cause, for example, restlessness, anxiety and delusions. The neurotransmitter dopamine plays an important role in this process. Perphenazine is classified as a neuroleptic, which has a depressant effect on the human nervous system. It belongs to the phenothiazines, which have the effect of classic neuroleptics. Thus, the drug influences the interaction of the different nerve cells as well as their interconnections. Perphenazine acts as an antagonist to dopamine, whose binding sites are blocked by it. Perphenazine is not only strong, but also fast-acting. Its dopamine-inhibiting effect ensures the attenuation of symptoms resulting from psychosis, as well as nervousness and restlessness. Animal studies showed stronger effects of perphenazine than chlorpromazine. The neuroleptic mode of action can be compared to haloperidol. If perphenazine is used in higher doses, the neurotransmitters adrenaline and histamine, which influence the autonomic nervous system, are also inhibited. In this way, movement disorders, which are among the symptoms of schizophrenic psychosis, can be reduced. In addition, the neuroleptic affects the neurotransmitter acetylcholine. This neurotransmitter is important for muscle movement. The action of perphenazine can reduce muscle twitching that occurs during psychotic episodes. Due to the influence on acetylcholine, the activity of the intestine as well as the salivation are also stimulated. For this reason, the drug is also considered effective against nausea and vomiting. Perphenazine’s bioavailability is 40 percent, while its plasma half-life is between 8 and 12 hours. Metabolism of the neuroleptic occurs via the liver.
Medical use and application
The main use of perphenazine is in the treatment of psychotic disorders such as acute psychosis. In this context, the neuroleptic has an alleviating effect on severe mood swings that occur in the context of manias, hallucinations, and delusions. These usually result from a psychotic episode. Furthermore, perphenazine serves to alleviate pronounced muscle twitching during an acute schizophrenia attack. Thus, schizophrenia is one of the most common forms of psychosis. Since the neuroleptic also has sedative properties, it can also be administered for nervousness. The indications for perphenazine also include nausea and vomiting, for which it is administered as an alternative. This means that other means for this purpose were not effective in advance. The active substance is administered by taking tablets or drops. It is also possible to administer it as an injection solution in an ampoule. The recommended dose of perphenazine is 4 to 8 milligrams administered up to three times a day. In this context, the drug is also suitable for long-term therapy, although this increases the risk of tardive dyskinesia.
Risks and side effects
The use of perphenazine may result in the occurrence of adverse side effects. The most common side effects include drowsiness, sleep disturbances, drowsiness, fatigue, dizziness, restlessness, dyskinesias (involuntary head movements), the jerky advancement of the tongue, movement disorders, stiffness of the muscles, involuntary movements of the face, tremors, and lack of movement.Other common side effects include orthostatic regulation disorders of the circulatory system, cardiac arrhythmias, increased heartbeat, low blood pressure, an increase in blood prolactin levels, breast tenderness, menstrual disorders and milk flow, bronchial asthma, impotence, and orgasmic disorders. In some patients, a malignant neuroleptic syndrome sets in during perphenazine therapy, which can assume life-threatening proportions. It is manifested by muscle rigidity, palpitations, circulatory collapse, fever, excessive blood pressure, and clouding of consciousness. Even a coma is possible. At the beginning of the treatment, muscle cramps sometimes appear in the arms, neck, mouth and face, which in turn affects facial expressions. If the patient is hypersensitive to perphenazine or other phenothiazines, the drug must not be used. The same applies after acute intoxication with alcohol, sleeping pills or pain medication. Careful consideration of treatment with perphenazine by the physician is required if the patient suffers from pronounced liver dysfunction, cardiac impairment, diseases of blood and bone marrow, breast cancer, a tumor in the pituitary gland, orthostatic circulatory disorders, asthma, permanent respiratory problems, depression or constrictions in the gastrointestinal tract. The same applies in the presence of seizure disorders such as epilepsy. If there is hyperthyroidism, the physician must carefully monitor the patient. If administration of perphenazine is considered during pregnancy, it is important for the physician to weigh the benefits and risks of treatment. For example, animal studies showed damage to the child when the drug was used, so it should be taken only in exceptional cases. Moreover, because perphenazine passes into breast milk and has a harmful effect on the child, breastfeeding must be avoided during therapy.
