Enfuvirtide (Subcutaneous route)



Brand Names:

  • Fuzeon

Dosage Forms:

  • Powder for Solution



Antiretroviral Agent


HIV Fusion Inhibitor

Uses of This Medicine:

Enfuvirtide injection is used in combination with other antiviral medicines to treat human immunodeficiency virus (HIV) infection. HIV is the virus that causes acquired immunodeficiency syndrome (AIDS).

Enfuvirtide will not cure or prevent HIV infection or AIDS. It helps keep HIV from reproducing and appears to slow down the destruction of the immune system. This may help delay the development of problems usually result from AIDS or HIV disease. Enfuvirtide will not keep you from spreading HIV to other people. People who receive this medicine may continue to have some of the problems usually related to AIDS or HIV disease.

This medicine is available only with your doctor's prescription.

Before Using This Medicine:

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:


Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.


Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of enfuvirtide injection in children 6 years of age and older and weighing 11 kilograms (kg) or more. Safety and efficacy have been established.

Older adults—

Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of enfuvirtide injection in the elderly. However, elderly patients are more likely to have age-related kidney, liver, or heart problems, which may require caution in patients receiving this medicine.


There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Other medicines—

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Tipranavir

Other interactions—

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other medical problems—

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

  • Bleeding disorder (eg, hemophilia) or
  • Blood clotting problems—Use with caution. May increase bruising or bleeding after injection.
  • Lung or breathing problems (eg, pneumonia), history of—Use with caution. May make this condition worse.

Proper Use of This Medicine:

A nurse or other trained health professional will give you this medicine. It is given as a shot under your skin, usually in the stomach, upper arm, or thighs. You or your caregiver may be trained to prepare and inject this medicine at home. Be sure that you understand how to use the medicine.

If you use this medicine at home, you will be shown the body areas where this shot can be given. Use a different body area each time you give yourself a shot. Keep track of where you give each shot to make sure you rotate body areas. This will help prevent skin problems from the injections. Do not inject into skin areas near your elbow, knee, groin, lower or inner buttocks, into your navel (belly button), or into any skin areas where you have a mole, scar, bruise, tattoo, or burn.

This medicine comes with a patient information leaflet and patient instructions. Read and follow these instructions carefully. Ask your doctor if you have any questions.

Do not stop using this medicine without checking first with your doctor. When your supply of this medicine is running low, contact your doctor or pharmacist ahead of time. Do not allow yourself to run out of this medicine.

This medicine comes as a powder that must be mixed with sterile water before using. Use only the sterile water that came with your medicine to prepare it. Do not shake the medicine after adding the water. Gently tap the vial for 10 seconds and then roll it between your hands to avoid foaming. Wait for the powdered medicine to completely dissolve in the water before using it. This may take up to 45 minutes. Before using the medicine, make sure the solution is clear, colorless, has no bubbles or particles in it.

It is important to take enfuvirtide as part of a combination treatment. Be sure to take all the medicines your doctor has prescribed for you, including enfuvirtide.

Keep using this medicine for the full time of treatment even if you begin to feel better. If you stop the medicine even briefly, the virus may become harder to treat.


The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For injection dosage form (solution):
    • For treatment of HIV infection:
      • Adults—90 milligrams (mg) (1 milliliter [mL]) injected under the skin 2 times a day.
      • Children 6 years of age and older—Dose is based on weight and must be determined by your doctor.
        • Weighing 42.6 kilograms (kg) or more—90 milligrams (mg) (1 milliliter [mL]) injected under than skin 2 times a day.
        • Weighing 38.1 to 42.5 kg—81 mg (0.9 mL) injected under than skin 2 times a day.
        • Weighing 33.6 to 38.0 kg—72 mg (0.8 mL) injected under than skin 2 times a day.
        • Weighing 29.1 to 33.5 kg—63 mg (0.7 mL) injected under than skin 2 times a day.
        • Weighing 24.6 to 29.0 kg—54 mg (0.6 mL) injected under than skin 2 times a day.
        • Weighing 20.1 to 24.5 kg—45 mg (0.5 mL) injected under than skin 2 times a day.
        • Weighing 15.6 to 20.0 kg—36 mg (0.4 mL) injected under than skin 2 times a day.
        • Weighing 11.0 to 15.5 kg—27 mg (0.3 mL) injected under than skin 2 times a day.
      • Children younger than 6 years of age and weighing less than 11 kilograms (kg)—Use and dose must be determined by your doctor.

Missed dose—

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.


Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

After you mix the powder with the sterile water, you may use the mixture right away or store it in the refrigerator for up to 24 hours. Do not store the mixture in the syringe. If you use a mixture that has been kept in the refrigerator, allow it to reach room temperature before you inject it.

Throw away used needles in a hard, closed container where the needles cannot poke through. Keep this container away from children and pets.

Precautions While Using This Medicine:

It is very important that your doctor check you your child's progress at regular visits, especially during the first few weeks that you use this medicine. Blood and urine tests may be needed to check for any unwanted effects.

This medicine may cause serious allergic reactions, which can be life-threatening and require immediate medical attention. Tell your doctor right away if you have a rash, itching, hoarseness, trouble breathing or swallowing, or any swelling of your hands, face, or mouth after using this medicine.

This medicine may increase the risk of having pneumonia. This is more likely to occur if you smoke or have a history of lung disease. Check with your doctor right away if you have chest pain or tightness, cough, fever, chills, or troubled breathing.

This medicine can cause reactions at the injection site. Almost all people get injection site reactions with enfuvirtide. These reactions hurt and itch, and they are usually mild to moderate but can occasionally be severe. These reactions generally happen within the first week of treatment and as you keep using enfuvirtide. If the injection site nodules drain pus or cause redness that spreads or streaks from the sites, or you are worried about the reaction you are having, call your doctor right away.

Some people who have used Biojector® 2000 to inject this medicine have had shooting nerve pain and tingling lasting up to 6 months when injected close to large nerves or near joints, or had bleeding, bruising, or lumps. Talk to your doctor if you have concerns about this.

Your immune system may get stronger when you start using HIV medicines. Tell your doctor right away if you notice any changes in your health. Sometimes the immune system will start to fight infections that were hidden in your body, such as pneumonia, herpes, or tuberculosis. Autoimmune disorders (eg, Graves' disease, polymyositis, and Guillain-Barré syndrome) may also occur.

This medicine may make you dizzy or drowsy. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.

This medicine does not decrease the risk of transmitting the HIV infection to others through sexual contact or by contaminated blood. Make sure you understand and practice safe sex, even if your partner also has HIV. Avoid sharing needles with anyone.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Side Effects of This Medicine:

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common
burning, numbness, tingling, or painful sensations or weakness in the arms, hands, legs, or feet
pain or tenderness around the eyes and cheekbones
stuffy or runny nose
tightness of the chest
troubled breathing
Less common
dark urine
dry or itching eyes
excessive tearing
eye discharge
fast heartbeat
itching, pain, redness, swelling, tenderness, or warmth on the skin at the injection site
loss of appetite
lump or growth on the skin
pains in the stomach, side, or abdomen, possibly radiating to the back
redness, pain, swelling of the eye, eyelid, or inner lining of the eyelid
swollen, painful, or tender lymph glands in the neck, armpit, or groin
yellow eyes or skin
Difficulty in swallowing
skin itching, rash, or redness
swelling of the face, throat, or tongue
Incidence not known
Black, tarry stools
bleeding gums
blood in the urine or stools
chest pain
decreased frequency or amount of urine
inability to move the arms and legs
increased blood pressure
increased thirst
lower back or side pain
painful or difficult urination
pale skin
pinpoint red spots on the skin
sore throat
sudden numbness and weakness in the arms and legs
swelling of the face, fingers, lower legs
ulcers, sores, or white spots in the mouth
unusual bleeding or bruising
unusual tiredness or weakness
weight gain

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common
Abnormal growth filled with fluid or semisolid material
burning or stinging of the skin
decreased appetite
dry mouth
feeling sad or empty
hard lump
lack or loss of strength
large, flat, blue or purplish patches in the skin
muscle pain
painful cold sores or blisters on the lips, nose, eyes, or genitals
small lumps under the skin
trouble concentrating
trouble sleeping
unusually warm skin
weight loss
Less common
Bad, unusual, or unpleasant (after) taste
burning, itching, and pain in hairy areas
change in taste
general feeling of discomfort or illness
joint pain
pus at the hair root
stomach pain

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Last Updated: 6/18/2019

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites.

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The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites.
All rights reserved.

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