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Generic name: efavirenz, lamivudine and tenofovir disoproxil fumarate

What is Symfi?

Symfi is a prescription medicine that is used without other antiretroviral medicines to treat Human Immunodeficiency Virus-1 (HIV-1) in adults and children weighing at least 88 pounds (40 kg).

HIV-1 is the virus that causes AIDS (Acquired Immune Deficiency Syndrome).

Symfi contains the prescription medicines efavirenz, lamivudine and tenofovir disoproxil fumarate.

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

Symfi can cause serious side effects, including:

  • Worsening of Hepatitis B virus infection. If you have Human Immunodeficiency Virus type 1 (HIV-1) and Hepatitis B Virus (HBV) infection, your HBV may get worse (flare-up) if you stop taking Symfi. A “flare-up” is when your HBV infection suddenly returns in a worse way than before. Your healthcare provider will test you for HBV infection before you start treatment with Symfi.
    • It is not known if Symfi is safe and effective in people who have both HIV-1 and HBV infection.
    • Do not run out of Symfi. Refill your prescription or talk to your healthcare provider before your Symfi is all gone.
    • Do not stop Symfi without first talking to your healthcare provider. If you stop taking Symfi, your healthcare provider will need to check your health often and do blood tests regularly for several months to check your liver.

For more information about side effects, see “What are the possible side effects of Symfi?

Who should not take Symfi?

Do not take Symfi if you:

  • are allergic to efavirenz, lamivudine, tenofovir disoproxil fumarate, or any of the ingredients in Symfi. See the end of this Patient Information leaflet for a complete list of ingredients in Symfi.
  • are currently taking elbasvir and grazoprevir.

What should I tell my healthcare provider before taking Symfi?

Before you take Symfi, tell your healthcare provider about all of your medical conditions, including if you:

  • have liver problems, including hepatitis B or C infection
  • have kidney problems, including end-stage renal disease (ESRD) that requires dialysis
  • have a history of mental health problems
  • have a history of drug or alcohol abuse
  • have a heart problem, including QT prolongation
  • have bone problems, including a history of bone fractures
  • have a history of seizures
  • are pregnant or plan to become pregnant. Symfi may harm your unborn baby.
    • You should not become pregnant during treatment with Symfi. Tell your healthcare provider right away if you think you may be pregnant or become pregnant during treatment with Symfi.
    • Females who are able to become pregnant should use effective birth control during treatment with Symfi and for 12 weeks after stopping treatment. A barrier form of birth control should always be used along with another type of birth control.
    • If you are able to become pregnant, your healthcare provider should do a pregnancy test before you start Symfi.

      Pregnancy Registry. There is a pregnancy registry for women who take Symfi during pregnancy. The purpose of this registry is to collect information about the health of you and your baby. Talk to your healthcare provider about how you can take part in this registry.
  • are breastfeeding or plan to breastfeed. Do not breastfeed if you take Symfi.
    • You should not breastfeed if you have HIV-1 because of the risk of passing HIV-1 to your baby.
    • Talk to your healthcare provider about the best way to feed your baby.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins and herbal supplements.

Some medicines interact with Symfi. Symfi may affect the way other medicines work, and other medicines may affect how Symfi works. Keep a list of your medicines and show it to your healthcare provider and pharmacist when you get a new medicine.

  • You can ask your healthcare provider or pharmacist for a list of medicines that interact with Symfi.
  • Do not start taking a new medicine without telling your healthcare provider. Your healthcare provider can tell you if it is safe to take Symfi with other medicines.

How should I take Symfi?

  • Take Symfi exactly as your healthcare provider tells you to take it.
  • Take Symfi 1 time each day, preferably at bedtime. Taking Symfi at bedtime might help to make some of the side effects less bothersome.
  • Take Symfi on an empty stomach.
  • Do not miss a dose of Symfi. If you miss a dose, take the missed dose as soon as you remember. If it is almost time for your next dose of Symfi, do not take the missed dose. Take the next dose at your regular time.
  • Stay under the care of your healthcare provider during treatment with Symfi.
  • Do not run out of Symfi. The virus in your blood may increase and the virus may become harder to treat. When your supply starts to run low, get more from your healthcare provider or pharmacy.
  • If you take too much Symfi, go to the nearest hospital emergency room right away.

What should I avoid while taking Symfi?

You should avoid taking medicines that contain sorbitol during treatment with Symfi.

What are the possible side effects of Symfi?

Symfi may cause serious side effects, including:

  • See “What is the most important information I should know about Symfi?
  • Build-up of an acid in your blood (lactic acidosis). Lactic acidosis can happen in some people who take Symfi. Lactic acidosis is a serious medical emergency that can lead to death. Call your healthcare provider right away if you get any of the following symptoms that could be signs of lactic acidosis:
    • feel very weak or tired
    • unusual (not normal) muscle pain
    • trouble breathing
    • stomach pain with nausea or vomiting
    • feel cold, especially in your arms and legs
    • feel dizzy or lightheaded
    • have a fast or irregular heartbeat
  • Severe liver problems can happen in people who take Symfi. In some cases, these severe liver problems can lead to death. Your liver may become large (hepatomegaly) and you may develop fat in your liver (steatosis). Inflammation of your liver (hepatitis) that can lead to liver failure requiring a liver transplant has been reported in some people treated with Symfi. Your healthcare provider may do blood tests to check your liver before and during treatment with Symfi.
    Call your healthcare provider right away if you get any of the following signs or symptoms of liver problems:
    • your skin or the white part of your eyes turns yellow (jaundice)
    • dark or “tea-colored” urine
    • light-colored stools (bowel movements)
    • confusion
    • tiredness
    • loss of appetite for several days or longer
    • nausea and vomiting
    • pain, aching, or tenderness on the right side of your stomach-area
    • weakness
    • stomach (abdomen) swelling
      You may be more likely to get lactic acidosis or serious liver problems if you are female or very overweight (obese).
  • New or worse kidney problems, including kidney failure. Your healthcare provider may do blood and urine tests to check your kidneys before and during treatment with Symfi. Tell your healthcare provider if you get signs and symptoms of kidney problems, including bone pain that does not go away or worsening bone pain, pain in your arms, hands, legs or feet, broken (fractured) bones, muscle pain or weakness.
  • Serious mental health problems.Get medical help right away if you get any of the following symptoms:
    • feel sad or hopeless
    • feel anxious or restless
    • do not trust other people
    • hear or see things that are not real
    • are not able to move or speak normally
    • have thoughts of hurting yourself (suicide) or have tried to hurt yourself or others
    • are not able to tell the difference between what is true or real and what is false or unreal
  • Nervous system symptoms are common in people who take Symfi and can be severe. These symptoms usually begin during the first or second day of treatment with Symfi and usually go away after 2 to 4 weeks of treatment. Some symptoms may occur months to years after beginning Symfi therapy. These symptoms may become worse if you drink alcohol, take a medicine for mental health problems, or use certain street drugs during treatment with Symfi. Symptoms may include:
    • dizziness
    • trouble sleeping
    • unusual dreams
    • trouble concentrating
    • drowsiness
    • lack of coordination or balance
      If you have dizziness, trouble concentrating or drowsiness, do not drive a car, use machinery, or do anything that needs you to be alert.

      Some nervous system symptoms (e.g., confusion, slow thoughts and physical movement, and delusions [false beliefs] or hallucinations [seeing or hearing things that others do not see or hear]) may occur months to years after beginning Symfi therapy. Promptly contact your health care provider should any of these symptoms occur.
  • Skin reactions and allergic reactions. Skin reactions or rash can happen and can sometimes be severe. Skin rash usually goes away without any change in treatment. If you develop a rash or a rash with any of the following symptoms, call your healthcare provider right away:
    • itching
    • fever
    • swelling of your face
    • blisters or skin lesions
    • peeling skin
    • mouth sores
    • red or inflamed eyes
  • Risk of inflammation of the pancreas (pancreatitis). Children may be at risk for developing pancreatitis during treatment with Symfi if they:
    • have taken nucleoside analogue medicines in the past
    • have a history of pancreatitis
    • have other risk factors for pancreatitis
      Call your healthcare provider right away if your child develops signs and symptoms of pancreatitis including severe upper stomach-area pain, with or without nausea and vomiting. Your healthcare provider may tell you to stop giving Symfi to your child if their symptoms and blood test results show that your child may have pancreatitis.
  • Seizures. Seizures are more likely to happen if you have had seizures in the past.
  • Increases in blood fat levels (cholesterol and triglycerides). Your healthcare provider will check your blood fat levels before and during treatment with Symfi.
  • Bone problems can happen in some people who take Symfi. Bone problems include bone pain, softening or thinning (which may lead to fractures). Your healthcare provider may need to do tests to check your bones. Tell your healthcare provider if you have any bone pain, pain in your hands or feet, or muscle pain or weakness during treatment with Symfi.
  • Changes in your immune system (Immune Reconstitution Syndrome) can happen when you start taking HIV-1 medicines. Your immune system may get stronger and begin to fight infections that have been hidden in your body for a long time. Tell your healthcare provider if you start having new symptoms after starting your HIV-1 medicine.
  • Changes in body fat can happen in some people who take HIV-1 medicines. These changes may include increased amount of fat in the upper back and neck (“buffalo hump”), breast, and around the main part of your body (trunk). Loss of fat from the legs, arms, and face may also happen. The cause and long-term health effects of these conditions are not known.
  • Changes in the electrical activity of your heart called QT prolongation. QT prolongation can cause irregular heartbeats that can be life-threatening. Tell your healthcare provider if you feel faint, lightheaded, dizzy, or feel your heart beating irregularly or fast during treatment with Symfi.

The most common side effects of Symfi are:

  • trouble concentrating
  • headache
  • not feeling well
  • nasal signs and symptoms
  • rash
  • trouble sleeping
  • depression
  • cough
  • abnormal dreams
  • nausea
  • tiredness
  • diarrhea
  • dizziness
  • pain
  • weakness

Tell your healthcare provider if you have any side effect that bothers you or that does not go away.

These are not all the possible side effects of Symfi. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

General information about the safe and effective use of Symfi

Medicines are sometimes prescribed for purposes other than those listed in a Patient Information leaflet. Do not use Symfi for a condition for which it was not prescribed. Do not give Symfi to other people, even if they have the same symptoms that you have. It may harm them. If you would like more information, talk with your healthcare provider. You can ask your pharmacist or healthcare provider for information about Symfi that is written for health professionals.

How should I store Symfi?

  • Store Symfi tablets below 86°F (30°C).
  • Keep Symfi tablets in the original container.

Keep Symfi and all medicines out of the reach of children.

What are the ingredients in Symfi?

Active ingredient: efavirenz, lamivudine, and tenofovir disoproxil fumarate

Inactive ingredients: croscarmellose sodium, hydroxypropyl cellulose, lactose monohydrate, magnesium stearate, microcrystalline cellulose, polyethylene glycol, polyvinyl alcohol, sodium chloride, sodium lauryl sulfate, talc and titanium dioxide.

For more information, call Mylan at 1-877-446-3679 (1-877-4-INFO-RX).

Source: National Library of Medicine. Last updated October 15, 2019.