Enfuvirtide is used along with other medications to treat human immunodeficiency virus (HIV) infection. Enfuvirtide is in a class of medications called HIV entry and fusion inhibitors. It works by decreasing the amount of HIV in the blood. Although enfuvirtide does not cure HIV, it may decrease your chance of developing acquired immunodeficiency syndrome (AIDS) and HIV-related illnesses such as serious infections or cancer. Taking these medications along with practicing safer sex and making other life-style changes may decrease the risk of transmitting (spreading) the HIV virus to other people.

Enfuvirtide comes as a powder to be mixed with sterile water and injected subcutaneously (under the skin). It is usually injected twice a day. To help you remember to inject enfuvirtide, inject it at about the same times each day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Use enfuvirtide exactly as directed. Do not use more or less of it or use it more often than prescribed by your doctor.

Enfuvirtide controls HIV but does not cure it. Continue to use enfuvirtide even if you feel well. Do not stop using enfuvirtide without talking to your doctor. If you miss doses or stop using enfuvirtide, your condition may become more difficult to treat.When your supply of enfuvirtide starts to run low, get more from your doctor or pharmacist.

You will receive your first dose of enfuvirtide in your doctor's office. After that, you can inject enfuvirtide yourself or have a friend or relative perform the injections. Your doctor will train the person who will be injecting the medication, and will test him to be sure he can give the injection correctly. Be sure that you and the person who will be giving the injections read the manufacturer's information for the patient that comes with enfuvirtide before you use it for the first time at home.

You can inject enfuvirtide anywhere on the front of your thighs, your stomach, or upper arms. Do not inject enfuvirtide in or near your navel (belly button) or in any area directly under a belt or waistband; near the elbow, knee, groin, the lower or inner buttocks; or directly over a blood vessel. To reduce the chances of soreness, choose a different area for each injection. Keep track of the areas where you inject enfuvirtide, and do not give an injection into the same area two times in a row. Use your fingertips to check your chosen area for hard bumps under the skin. Never inject enfuvirtide into any skin that has a tattoo, scar, bruise, mole, a burn site, or has had a reaction to a previous injection of enfuvirtide.

Never reuse needles, syringes, vials of enfuvirtide, or vials of sterile water. Dispose of used needles and syringes in a puncture-resistant container. Do not put them in a trash can. You can dispose of used alcohol pads and vials in the trash, but if you see blood on an alcohol pad, put it in the puncture-resistant container. Talk to your doctor or pharmacist about how to dispose of the puncture-resistant container.

Before preparing an enfuvirtide dose, wash your hands with soap and water. After you wash your hands, do not touch anything except the medication, supplies, and the area where you will inject the medication.

Ask your pharmacist or doctor for a copy of the manufacturer's injection information for the patient. Carefully read the manufacturer's instructions to learn how to prepare and inject your dose. Ask your doctor or pharmacist if you have questions about how to inject enfuvirtide.

Before using enfuvirtide,

• tell your doctor and pharmacist if you are allergic to enfuvirtide, mannitol, or any other medications.
• tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking. Be sure to mention anticoagulants ('blood thinners') such as warfarin (Coumadin).
• tell your doctor if you smoke, if you use or have ever used intravenous (injected into the vein) street drugs, and if you have or have ever had hemophilia or any other blood-clotting or bleeding condition, or lung disease.
• tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while using enfuvirtide, call your doctor. You should not breast-feed if you are infected with HIV or if you are using enfuvirtide.
• you should know that enfuvirtide may make you dizzy. Do not drive a car or operate machinery until you know how this medication affects you.

Inject the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not inject a double dose to make up for a missed one.

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Keep this medication and the sterile water that comes with it in the containers they came in, tightly closed, and out of reach of children. Store them at room temperature and away from excess heat and moisture (not in the bathroom). If they can not be stored at room temperature, put them in the refrigerator. If you mix the medication and sterile water in advance, store the mixture in the vial in the refrigerator for up to 24 hours. Never store mixed medication in the syringe.

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Unless your doctor tells you otherwise, continue your normal diet.

Enfuvirtide may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• itching, swelling, pain, tingling, discomfort, tenderness, redness, bruising, hardened area of skin, or bumps in the place where you injected enfuvirtide
• difficulty falling or staying asleep
• depression
• nervousness
• tiredness
• weakness
• muscle pain
• nausea
• loss of appetite
• changes in ability to taste food
• weight loss
• diarrhea
• constipation
• flu-like symptoms
• runny nose with sinus pain
• warts or cold sores
• swollen glands
• painful, red, or teary eyes

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately:

• severe pain, oozing, swelling, warmth, or redness in the place you injected enfuvirtide
• rash
• fever
• vomiting
• nausea with rash and/or fever
• chills
• fainting
• dizziness
• blurred vision
• cough
• difficulty breathing
• blood in urine
• swollen feet
• fast breathing
• shortness of breath
• pain, burning, numbness, or tingling in feet or legs
• pale or fatty stools
• yellowing of skin or eyes

Enfuvirtide may cause other side effects. Call your doctor if you have any unusual problems while using this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your body's response to enfuvirtide.

Before having any laboratory test, tell your doctor and the laboratory personnel that you are using enfuvirtide.

Do not let anyone else use your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

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