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What is Prolixon?


Prolixin (fluphenazine)

Prolixin is a phenothiazine antipsychotic agent that was developed in the 1960s.  It is indicated for the treatment of schizophrenia and is useful for treating positive symptoms such as hallucinations, delusions, bizarre behavior and hostility.   Prolixin is commonly used as the long acting injection (Depot) form in patients who tolerate an intramuscular injection better than taking oral medications.    The Depot injection can last up to 2 to 4 weeks before the next injection is needed.    Like most antipsychotic agents, Prolixin is effective for about 60 percent of those who try it.

What is the most important information I should know about Prolixin?

What should I discuss with my healthcare provider before taking Prolixin?

How should I take Prolixin?

Prolixin comes as a tablet or oral liquid (elixir and concentrate) to take by mouth. It can be   taken one to   three times a day and may be taken with or without food. Follow the directions on your prescription label carefully, and ask your health care provider to explain any part you do not understand. Take this medication exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Prolixin oral liquid comes with a specially marked dropper for measuring the dose. Ask your pharmacist to show you how to use the dropper. Do not allow the liquid to touch your skin or clothing; it can cause skin irritation. Dilute the concentrate in water, lemon-lime soda, carbonated orange beverage, milk, or V-8, pineapple, apricot, prune, orange, tomato, or grapefruit juice just before taking it. Do not use beverages containing caffeine (coffee, tea, and cola) or apple juice.

If you are receiving Prolixin Depot muscular injections you need to return every 2 – 4 weeks depending on your administration schedule.  Please inform your doctor if you experience any pain, redness or irritation in or around the site of injection.

Continue to take Prolixin even if you feel well. Do not stop taking Prolixin without talking to your doctor, especially if you have taken large doses for a long time. If your doctor recommends discontinuation of Prolixin therapy, it is usually best to   decrease your dose gradually. This drug must be taken regularly for a several weeks before its full effect is felt.  Some patients may take this medicine lifelong.

What happens if I miss a dose of Prolixin?

If a dose of Prolixin is missed, take it as soon as you remember to, if it is not too close to when your next dose is due.    Do not double up on your next dose.

What should I avoid while taking Prolixin?

What happens if I overdose with Prolixin?

What are the possible side effects of Prolixin?

Common adverse effects of Prolixin usually include sleepiness, dizziness, constipation, excessive saliva in mouth, and weight gain. An adverse effect that may occur is known as orthostatic hypotension (dizziness due to a lowering of your blood pressure when you sit up or stand up). Occasionally this can lead to fainting and falling down, therefore, people taking Prolixin should be careful when they change positions These adverse effects are usually mild and usually go away after the first several days of starting treatment or increasing a dose.

Prolixin has (30-40%) incidence of extrapyramidal symptoms such as muscle spasms, cramps, or posturing movements, and side effects such as restlessness, muscle rigidity, and tremor.

Are there any risks for taking Polixin for long periods of time?

Prolixin may cause tardive dyskinesia (see warnings above). TD is characterized by involuntary movements such as grimacing, sucking/smacking of lips, and spasmodic movements of the extremities. It usually begins after several months of treatment and may be irreversible. Same comment as above

If you experience any of the following symptoms, call your health care provider immediately:

What other drugs interact with Prolixin?

There are many other medications that may interact with Prolixin. Any other medication that causes sleepiness may increase the same side effects of Prolixin and increase your chances of unsteadiness and falling.  Others include: opioid analgesics, alcohol, antihistamines and tricyclic antidepressants.

How long does it take for Prolixin to work?

A patient should continue a trial of Prolixin for at least four to six weeks.   Some symptoms such as hallucinations, anxiety, paranoia, and bizarre behavior may start to improve within 1 – 2 weeks; however, it is important to continue treatment to observe the maximum beneficial effects.

Brand/Generic Names

Novartis manufactures and markets fluphenazine under the brand name Prolixin®. Generic forms of fluphenazine are marketed by Apothecon, Novex Pharma, and Bedford Laboratories.

Available forms…

  • Prolixin /Fluphenazine HCL tablets

1 mg,   2.5 mg,   5 mg, and   10 mg

  • Prolixin /Fluphenazine HCL Elixir

0.5 mg/ml  (2.5mg / 5ml teaspoon)   60 ml and 473 ml bottles

5 mg/ml (concentrate) 60 ml and 473 ml bottles

  • Prolixin® /Fluphenazine HCL injection (short acting injection)

2.5mg/ml    5 ml vial

  • Prolixin /Fluphenazine Decanoate (long acting injection)

25mg/ml     Multidose 5ml vial and single dose 1ml vial

Updated by Mark E. Schneiderhan, PharmD  
March 2007


Tardive Dyskinesia (TD)

Prolixin may cause tardive dyskinesia (TD), a potentially permanent side effect of antipsychotic medications. TD is characterized by movements you may be unable to control such as grimacing, smacking of lips, tongue darting or rolling and movements of the extremities. Sometimes you may not notice that you are doing these movements. TD usually begins after several months of treatment and may be irreversible. However, if TD is caught early, it may be reversible. If you develop these symptoms, call your healthcare provider immediately.

Neuroleptic Malignant Syndrome (NMS)

Neuroleptic malignant syndrome “NMS” is a rare, life-threatening, neurological disorder most often caused by an adverse reaction to antipsychotic medications. Symptoms of “NMS” include sudden high fever, sweating, changing blood pressure, dizziness, fatigue, muscle stiffness, as well as changes in liver & kidney function.  In most cases, the disorder develops within the first 2 weeks of medication treatment.   Early identification of and treatment for individuals with neuroleptic malignant syndrome slows the progression and improves recovery from “NMS”. A different antipsychotic can be reintroduced very slowly once recovery is complete, although there is a risk that the syndrome might recur. Notify your healthcare provider immediately if you suspect you are developing “NMS”.