A first-generation antipsychotic, also used for severe nausea
Perphenazine
A first-generation antipsychotic used for conditions such as schizophrenia, and also to treat severe nausea and vomiting.
What is Perphenazine?
Perphenazine is a first-generation (typical) antipsychotic used to treat conditions such as schizophrenia and to help control severe anxiety, agitation and disturbed behaviour. It is also used at lower levels to treat severe nausea and vomiting. It is taken by mouth as tablets. Like other older antipsychotics, it can cause movement-related side effects (such as stiffness, restlessness or tremor), drowsiness and a drop in blood pressure, and it can raise the hormone prolactin and affect the heart's rhythm (the QT interval). It is used under medical supervision with attention to these effects.
Education and reference only. This is a plain-language guide to Perphenazine — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Perphenazine is a first-generation, or 'typical', antipsychotic, one of the older group of medicines used to treat serious mental-health conditions. It is used mainly for psychotic illnesses such as schizophrenia, and to help with severe anxiety, agitation and disturbed or aggressive behaviour. It also has a separate, more limited use in treating severe nausea and vomiting. It is taken by mouth as tablets. Because it is an older antipsychotic, it tends to cause more movement-related side effects than newer ones, so it is used carefully and reviewed regularly.
How it works
Perphenazine works mainly by blocking dopamine, a chemical messenger in the brain. In conditions such as schizophrenia, an overactivity of dopamine signalling is linked to symptoms like hallucinations and disordered thinking, so blocking it helps calm these symptoms. The same dopamine-blocking action in a part of the brain that controls vomiting is why it can also treat severe nausea and sickness. However, blocking dopamine in the brain's movement-control areas explains the movement-related side effects, and its effect on dopamine elsewhere can raise the hormone prolactin, which is one of the things watched for during treatment.
Company & origin
Originated / developed by: Generic (long-established).
A long-established first-generation antipsychotic used in the UK for conditions such as schizophrenia, and also to treat severe nausea and vomiting.
What it treats
Conditions Perphenazine is used for
Practical use
How to take Perphenazine
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Take it regularly as prescribed, even when you feel well, and do not stop it suddenly without advice.
- Get up slowly from sitting or lying down, as it can lower your blood pressure and cause dizziness.
- Report any new muscle stiffness, tremor, restlessness or unusual movements to your prescriber promptly.
- Be careful with activities such as driving until you know how drowsy it makes you.
- Tell your prescriber about any heart-rhythm problems or other medicines, as some can affect the heart together with it.
Weighing it up
Advantages & disadvantages of Perphenazine
Advantages
- An effective, long-established treatment for psychotic illnesses such as schizophrenia.
- Also useful for treating severe nausea and vomiting and severe agitation.
- Taken by mouth as tablets, with decades of experience behind its use.
Disadvantages
- Tends to cause more movement-related (extrapyramidal) side effects than newer antipsychotics.
- Commonly causes drowsiness and can lower blood pressure, causing dizziness.
- Can raise the hormone prolactin and affect the heart's rhythm (the QT interval).
Practical use
Good to know
Because perphenazine is an older antipsychotic, its most characteristic side effects are movement-related, known as extrapyramidal effects: these include muscle stiffness, tremor, slowed movement and a distressing restlessness, and rarely repetitive movements that can become long-lasting, so any new movement problems should be reported. It commonly causes drowsiness and can lower blood pressure, particularly on standing, which can cause dizziness, so getting up slowly helps. It can raise the hormone prolactin, leading to effects such as breast changes or menstrual changes, and it can affect the heart's electrical rhythm (the QT interval), so the heart may be checked. As with all antipsychotics, it should not be stopped suddenly without advice. It is used with particular caution in older people, especially those with dementia, where antipsychotics carry added risks.
Who should not take it / use with caution
- People who have had a serious allergic reaction to perphenazine or similar antipsychotics should not take it.
- It is used with great caution, or avoided, in older people with dementia, where antipsychotics carry added risks.
- It is used cautiously in people with heart-rhythm problems, Parkinson's disease, or certain blood disorders.
- It is used with care in people with serious liver problems or a history of low blood pressure.
Monitoring
- Watching for movement-related side effects, drowsiness and dizziness from low blood pressure.
- Checking the heart's rhythm where needed, and reviewing prolactin-related effects.
- Reviewing how well symptoms are controlled and whether the treatment is still suitable.
Side effects
- Movement-related effects such as stiffness, tremor, slowed movement and restlessness.
- Drowsiness, a drop in blood pressure on standing, and dizziness.
- Raised prolactin, leading to breast or menstrual changes, and weight changes.
- Rarely but seriously, irregular heart rhythm, a severe reaction with high fever and stiffness, or long-lasting repetitive movements, which need urgent attention.
Key interactions
- Combining it with other medicines that affect the heart's QT interval increases the risk of rhythm problems.
- Alcohol and other sedating medicines add to its drowsiness and lowering of blood pressure.
- It can interact with Parkinson's medicines and some blood-pressure medicines, so tell your prescriber everything you take.
Available as: Tablets taken by mouth.
Answers
Perphenazine: frequently asked questions
What is perphenazine used for?
It is a first-generation antipsychotic used for conditions such as schizophrenia and for severe agitation, and it is also used to treat severe nausea and vomiting.
What are the movement side effects?
Being an older antipsychotic, it can cause stiffness, tremor, slowed movement and a distressing restlessness, and rarely long-lasting repetitive movements; report any new movement problems promptly.
Why do I feel dizzy when I stand up?
It can lower your blood pressure, especially on standing, which causes dizziness; getting up slowly from sitting or lying down helps reduce this.
Does it affect the heart?
It can affect the heart's electrical rhythm (the QT interval), so your prescriber may check your heart and review other medicines that do the same.
Can I stop it once I feel better?
No. Stopping an antipsychotic suddenly can cause problems and your symptoms may return, so only change or stop it on your prescriber's advice.
The wider class
About First-generation (typical) antipsychotic
Perphenazine belongs to the first-generation (typical) antipsychotic class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
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Authoritative sources
- BNF
- NICE CKS
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