Medication Search​ - Fuzeon

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How does Fuzeon work? What will it do for me?

Enfuvirtide belongs to the class of medications known as HIV fusion inhibitors. It is used in combination with other antiretroviral medications to treat the infection caused by the human immunodeficiency virus (HIV) for people whose current medication therapy is not working. HIV is the virus responsible for acquired immune deficiency syndrome (AIDS). HIV infection destroys CD4 (T) cells, which are important to the immune system. The immune system helps fight infections.

Enfuvirtide works by interfering with the entry of HIV into human cells. It does this by preventing the virus from joining with the human cell. Enfuvirtide lowers the amount of HIV in the blood and may also help the immune system by increasing the number of CD4 (T) cells in the body.

This medication does not cure AIDS and does not reduce the risk of passing HIV to others through sexual contact or blood contamination.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

What form(s) does Fuzeon come in?

Each single-use vial of white-to-off-white, sterile, lyophilized powder contains enfuvirtide 108 mg. Reconstitution with sterile water for injection yields a 90 mg/mL solution of enfuvirtide. Nonmedicinal ingredients: hydrochloric acid, mannitol, sodium carbonate, and sodium hydroxide.

How should I use Fuzeon?

Adult dosage: The recommended adult dose of enfuvirtide is 90 mg (1 mL) injected subcutaneously (under the skin) in the upper arm, upper thigh, or abdomen twice a day. The injection should be given at a different site each time and where there is no rash, redness, or pain. Do not inject the medication into moles, scar tissue, bruises, the navel (belly button), or areas that could be irritated by a belt or waistline of your clothes.

Children’s dosage: For children 6 to 16 years old, the dosage is based on body weight. The recommended dose of enfuvirtide is 2 mg per kilogram of body weight (to a maximum of 90 mg per dose) injected under the skin in the upper arm, upper thigh, or abdomen twice a day.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

Enfuvirtide should never be used on its own and should always be used in combination with other HIV medications.

Your doctor or health care provider will show you how to use this medication. Follow their directions and make sure you understand how to use the medication before you begin. If you have any questions, contact your health care provider.

Enfuvirtide must only be mixed with 1.1 mL of sterile water for injection. After adding the water, the vial should be gently tapped for 10 seconds and then allowed to stand until the powder completely dissolves. This could take up to 45 minutes. Only use the solution if it appears clear, colourless, and without bubbles or particles. The mixed solution should be injected immediately or stored in the refrigerator and used within 24 hours. The refrigerated solution should be brought to room temperature before injection and should only be used if the solution appears clear, colourless, and without bubbles or particles.

It is important to use this medication exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

The powder for the solution should be stored at room temperature (15°C to 30°C). The reconstituted solution (the powder mixed with sterile water) should be stored in the refrigerator (2°C to 8°C) for no longer than 24 hours.

Keep this medication out of the reach of children. Safely dispose of any unused portions remaining in the single-use vial.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Who should NOT take Fuzeon?

Do not use this medication if you are allergic to enfuvirtide or any ingredients of the medication.

What side effects are possible with Fuzeon?

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

  • constipation
  • cough
  • decreased appetite or loss of appetite
  • difficulty sleeping
  • dizziness
  • fatigue or tiredness
  • headache
  • injection site reactions, e.g.:
    • hardening of the skin
    • itching
    • pain
    • redness
    • swelling
    • tenderness
  • nausea
  • skin rash
  • weakness

Although most of the side effects listed below don’t happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

  • injection site reactions that are severe enough to limit your daily activities
  • muscle pain or cramps
  • numbness or tingling of arms, legs, or feet
  • signs of depression (e.g., poor concentration, changes in weight, changes in sleep, decreased interest in activities, thoughts of suicide)
  • signs of increased blood sugar (e.g., persistent thirst, frequent need to urinate)
  • signs of pneumonia (e.g., fever with a cough, shortness of breath, rapid breathing)
  • sinus infections
  • swollen glands
  • weight loss

Seek immediate medical attention if any of the following occur:

  • signs of an allergic reaction, e.g.:
    • hives
    • shortness of breath or difficulty breathing
    • swelling of the eyes, mouth, lips, or throat
  • signs of pancreatitis, e.g.:
    • abdominal pain on the upper left side
    • back pain
    • chills
    • fever
    • nausea
    • rapid heartbeat
    • swollen abdomen

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Are there any other precautions or warnings for Fuzeon?

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Diabetes: Enfuvirtide may cause increased blood glucose levels, causing decreased diabetes control. If you have diabetes, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Hypersensitivity reaction: Enfuvirtide may cause hypersensitivity reactions for some people. If you experience symptoms such as rash, fever, nausea, vomiting, chills, tremors, or severe dizziness, you should get medical attention right away.

Immune reconstitution inflammatory syndrome: This medication may cause immune reconstitution syndrome, where signs and symptoms of inflammation from previous infections appear. These symptoms occur soon after starting anti-HIV medication and can vary. They are thought to occur as a result of the immune system improving and being able to fight infections that have been present without symptoms (such as pneumonia, herpes, or tuberculosis). Report any new symptoms to your doctor immediately.

Pneumonia: People taking enfuvirtide may have a higher risk of pneumonia caused by bacteria. If you have risk factors for pneumonia, such as being a smoker, using IV drugs, or having previous lung disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

If you see signs of pneumonia (e.g., coughing, fever, shortness of breath, and chest pain) while taking this medication, contact your doctor as soon as possible.

Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.

Breast-feeding: It is not known if enfuvirtide passes into breast milk. Women who have HIV infection are cautioned against breast-feeding because of the risk of passing HIV to a baby who does not have the infection.

Children: The safety and effectiveness of using this medication have not been established for children less than 6 years of age.

What other drugs could interact with Fuzeon?

There may be an interaction between enfuvirtide and any of the following:

  • protease inhibitors (e.g., darunavir, lopinavir, ritonavir, saquinavir, tipranavir)

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

  • stop taking one of the medications,
  • change one of the medications to another,
  • change how you are taking one or both of the medications, or
  • leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.

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