Nov 23rd 2022
Fluphenazine Decanoate is a typical, first-generation antipsychotic drug, of the phenothiazine class, used to treat schizophrenia. You should always consult with your doctor if you are taking any other medications, have allergies, or have been diagnosed with other medical conditions, as misuse of Fluphenazine can have dangerous consequences.
Fluphenazine decanoate is commonly sold under the following brand names:
Fluphenazine decanoate is primarily used to treat patients with schizophrenia.It is delivered through a long-acting injection, and used for maintenance therapy. For most patients, fluphenazine decanoate can control schizophrenic symptoms 4 week or longer. 
Fluphenazine decanoate blocks dopamine receptors in the brain. It is believed that this mechanism helps to treat symptoms of psychosis, such as hallucinations and delusions, that are related to a chemical imbalance with the dopamine neurotransmitter. 
Fluphenazine decanoate is administered by a healthcare provider through an intramuscular injection (in the muscle) or subcutaneous injection (underneath the skin).  The gluteal muscle is the most common injection site. Doses range from 12.5mg to 100mg every two to five weeks.  The usual starting dose is between 12.5mg and 25mg.  The most common frequency is every four weeks. 
Fluphenazine decanoate is sometimes prescribed after you have been on a stable dose of the oral form of fluphenazine for a period of time, in order to minimize the risk of serious adverse reactions. 
Your doctor will carefully monitor your symptoms and adjust your dose as needed. They will also monitor for potentially serious adverse effects, as they can be unpredictable. If you miss an appointment for a scheduled dose, make a new one as soon as possible.
Fluphenazine decanoate usually begins to work within the body between 24 and 72 hours after injection, but it usually takes 48 to 96 hours for effects to become noticeable.  Effects of fluphenazine decanoate last around four weeks on average. 
The half-life of fluphenazine decanoate is 6.8 to 9.6 days.  This increases to 14.3 days after multiple injections.  Half-life is the time it takes for the medication in your system to decrease by half. It is still detectable in plasma up to six months after the last injection. 
Fluphenazine decanoate can cause adverse reactions in some people. Listed below are some of the most common side effects.
Tardive dyskinesia is a relatively rare condition that can occur with continued use of antipsychotic drugs. It can cause repetitive, involuntary movements, especially in the mouth, face, neck, arms, and legs. Consult with your doctor if you notice the following signs:
Neuroleptic Malignant Syndrome is a rare but potentially fatal condition that can occur when taking antipsychotics. Seek immediate medical attention if you experience the following symptoms:
Rarely, fluphenazine decanoate can lead to high prolactin levels. Too much of this hormone can decrease the production of estrogen and testosterone, which can cause:
If you experience mild side effects that are bothersome or do not subside, contact your doctor to discuss your options. If you notice any severe side effects, seek immediate medical care from your doctor or the nearest emergency room.
Before taking this medication, tell your healthcare provider if you are pregnant or breastfeeding. Tell them about any allergies, especially to other phenothiazines, such as chlorpromazine or perphenazine, as fluphenazine can cause severe allergic reactions.  Inform your doctor of any other medications you are taking, and if you have a history of any medical conditions, including:
When you first start taking this medication, avoid driving or operating heavy machinery until you know how it affects you. Avoid getting up too fast, as you may experience dizziness or a drop in blood pressure.
While taking this medication, you should avoid alcohol, tobacco, and marijuana.  You should avoid extreme heat, as fluphenazine decanoate can increase the risk of heat stroke.  Use sunscreen and limit your time in the sun, as this medication can also increase sun sensitivity. 
The following medications are known to have potentially dangerous interactions with fluphenazine decanoate. Please note that this list is not exhaustive and only lists the most severe drug interactions. Always inform your doctor of all other medications you are taking.
While taking fluphenazine decanoate, your pharmacy or healthcare provider will store the drug between injection appointments. It will be stored at room temperature, away from moisture or light.  Your healthcare provider will check for any debris or changes in color of the liquid before administering. 
Overdoses of fluphenazine decanoate are uncommon, as the medication is administered by a healthcare provider. However, if it does occur, symptoms could include:
Although rare, there have been cases of death from overdose , so it’s important to seek immediate help from your physician or at your nearest emergency room. Following an overdose, your doctor will stop all injections until you show signs of relapse. Then, the dosage will be decreased. 
Flupenthixol and fluphenazine are two different typical antipsychotic drugs with similar properties. They both have similar effects on psychotic symptoms, but fluphenazine is stronger. A 25mg dose of fluphenazine decanoate is roughly equivalent to a 40mg dose of flupenthixol decanoate.