Last reviewed:
Nov 23rd 2022
PharmD, BCPS
Perphenazine is an antipsychotic medication used in the treatment of schizophrenia and other psychotic disorders. It belongs to a class of medications called first-generation or typical antipsychotic drugs, which should be taken as prescribed because they can cause severe adverse effects.[1]
Perphenazine is found under the following brand names [2]:
As a typical antipsychotic, perphenazine is most often prescribed for the treatment of schizophrenia. It is also effective for treating severe nausea and vomiting and may be prescribed for this purpose [2].
Typical antipsychotics like perphenazine may also be prescribed for the following conditions [1]:
Perphenazine works to treat psychosis and other symptoms of schizophrenia because of its actions on a brain chemical called dopamine. In people with symptoms of psychosis, dopamine levels are believed to be too high. Therefore, perphenazine and other first-generation antipsychotics block the activity of dopamine in the brain, reducing psychotic symptoms arising from elevated dopamine activity.[1]
Perphenazine is typically taken orally in pill form. Patients often take oral tablets 4 to 8 mg three times per day. The medication can also be administered parenterally, which means it is injected into the body.[1]
A patient’s dosing regimen can vary based on their unique needs, health status, and the severity of their condition. A doctor will determine the best dose for each individual patient and will provide instructions for how to take perphenazine.
Perphenazine has a half-life of 8-12 hours, with an average of 9.5 hours. In some cases, the half-life may be as long as 20 hours.[4] The half-life of a medication refers to the length of time it takes for half of one dose to be removed from the body.[5]
This means after about 9.5 hours, the concentration of perphenazine decreases to half the initial dose taken. A drug is eliminated from the body after 4 to 5 half-lives [5], so you can expect perphenazine to stay in your system for an average of about 38 to 47.5 hours, or between 1 ½ to two days.
First-generation or typical antipsychotics like perphenazine can have several side effects, which are described in more detail below.
The following common side effects are relatively mild with perphenazine and often are not serious and do not require medical attention[2]:
If the above side effects persist, are severe, or begin to interfere with daily functioning, talk with your doctor, who can advise you on the best course of action.
While the following side effects may not be as common, they are considered severe. Contact your doctor immediately or seek medical attention if you experience any of the following [2]:
Before taking perphenazine, it’s important to tell your doctor if you have any other health conditions or are using any other medications. Sometimes, perphenazine can be dangerous, depending on your particular health condition. It can also interact negatively with other medications you might be taking.
If you have liver disease, brain damage, trouble maintaining balance, or conditions that affect your blood cells, it may be unsafe for you to take perphenazine. Perphenazine can also cause problems when taken during pregnancy, so it’s important to tell your doctor if you’re pregnant or planning to become pregnant.[2]
Other health conditions that may make it dangerous for you to take perphenazine include a tumor on the gland near the kidneys, a history of seizures, breast cancer, an abnormal EEG, asthma, emphysema, lung infection, heart disease, or kidney disease.[2]
Other precautions to consider are that perphenazine can make you tired, so it’s important to wait to see how this medication affects you before you drive or operate heavy machinery. It may be unsafe to consume alcohol while on perphenazine, as it can worsen side effects. You may also be more sensitive to sunlight when taking the medication and overheat when exposed to extreme heat or when exercising vigorously.[2]
The list herein is not exhaustive. Talk with your doctor about any precautions you should know or follow when taking perphenazine.
Perphenazine may interact with other medications you are taking, so it’s important to be aware of potential interaction effects. The following medications may interact with perphenazine [2]:
The above list is not exhaustive, but these medications may interact with perphenazine. Be sure to talk to your doctor about these or any other medications you are taking.
If you’re taking a medication that could interact with perphenazine, your dose may need to be adjusted, or your doctor may carefully monitor you for side effects. In some situations, perphenazine may not be suitable for you if you must take a medication that could interact with it.
Perphenazine should be stored in its original prescription container to prevent someone from mistakenly taking this medication. The container should be tightly sealed, and it should be kept away from excessive heat or moisture. A bathroom is not an ideal location to store perphenazine.[2]
Taking too high of a dose of perphenazine can result in overdose symptoms, including the following [2]:
If a person has overdosed on perphenazine and collapsed, has a seizure, or cannot breathe, it is critical to call 9-1-1 or seek immediate medical attention.
People commonly have the following question about perphenazine:
Both perphenazine and fluphenazine belong to the first-generation or typical antipsychotic class of drugs. Some research suggests that perphenazine may be more effective than fluphenazine, but the two medications have a similar risk of causing side effects.[6]
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