Symtuza (Darunavir, Cobicistat, Emtricitabine, and Tenofovir Alafenamide) - Oral


Stopping Symtuza (darunavir, cobicistat, emtricitabine, and tenofovir alafenamide) suddenly has resulted in worsening hepatitis b virus (HBV) in people co-infected with HIV and HBV. If you have HBV and stop taking this medication, your liver function may need to be monitored for several months afterward.

What Is Symtuza?

Symtuza is a combination drug that comes in a single-tablet regimen used to treat HIV infection. It is an antiretroviral made up of the drug classes of protease inhibitors, nucleoside reverse transcriptase inhibitors, and cytochrome P450 (CYP450 )inhibitors.

This drug contains the following as active ingredients: 

  • Darunavir
  • Cobicistat
  • Emtricitabine
  • Tenofovir alafenamide

Darunavir, a protease inhibitor, targets and attaches to a specific part of the HIV protease, inhibiting its activity and stopping the maturation of HIV cells. This reduces the amount of HIV in the blood.

Cobicistat is a CYP450 inhibitor. It works as a boosting agent, as it lowers the viral load by boosting darunavir levels in your body. Emtricitabine and tenofovir alafenamide are nucleoside reverse transcriptase inhibitors. They stop the virus from multiplying.

This combination drug is available by prescription as a tablet to be taken by mouth.

Drug Facts

Generic Name: Darunavir, cobicistat, emtricitabine, tenofovir alafenamide

Brand Name(s): Symtuza

Drug Availability: Prescription

Administration Route: Oral

Therapeutic Classification: Antiretroviral agent

Available Generically: No

Controlled Substance: N/A

Active Ingredient: Darunavir, cobicistat, emtricitabine, tenofovir alafenamide

Dosage Form(s): Tablet

What Is Symtuza Used For?

Symtuza is a once-daily drug that treats HIV infection. It is used in adults and children weighing 40 kilograms (about 88 pounds) or more. It is not recommended in people with severe kidney or severe liver problems.

Additionally, Symtuza should not be used in children under 3 years old, weighing less than 10 kilograms (about 22 pounds), due to an increased risk of death.

How to Take Symtuza

Take once daily with food, as taking it with a meal will help your body better absorb it.

You may break the pill in half with a pill cutter for children or others who cannot swallow the tablet whole. However, you must take the entire dose once broken in half; do not save one half for later.

Keep taking your medication as prescribed, even if you feel better. Do not miss or skip any doses. Stopping Symtuza can cause an existing hepatitis B infection to worsen, so you should always consult with your healthcare provider before ending treatment.


It is recommended to store Symtuza at room temperature (68 F to 77 F) in a dry place away from moisture. However, you may keep it between cool and mildly hot temperatures (59 F to 86 F) temporarily. Do not store it in your bathroom.

Leave this drug tightly closed in its original container. Also, do not remove the anti-moisture packet inside the container. Keep it out of reach of children and pets.

Toss unused and expired drugs. Do not flush them down the toilet or pour them down the drain unless otherwise instructed. Ask your pharmacist about the best ways to dispose of medications. Check out drug disposal programs in your area.

How Long Does Symtuza Take to Work?

According to one clinical trial of 109 participants, 84% of those who rapidly initiated treatment with Symtuza (within two weeks of HIV diagnosis) achieved undetectable viral loads at 48 weeks. An undetectable viral load occurs when copies of HIV cannot be detected by standard viral load tests in people with HIV. This is typically the goal of treatment.

What Are the Side Effects of Symtuza?

This is not a complete list of side effects, and others may occur. A healthcare provider can advise you on side effects. If you experience other effects, contact your healthcare provider. You may report side effects to the FDA at or 1-800-FDA-1088.

Common Side Effects

Symtuza may or may not cause side effects in some people. Contact your healthcare provider immediately if your side effects do not go away or become irritating. The following are some common side effects of Symtuza:

Severe Side Effects

Immediately inform your healthcare provider if you experience any serious adverse effects. Call 911 if you have any life-threatening symptoms that may require emergency medical attention.

Severe side effects of Symtuza include:

  • Swollen gland
  • Change in body fat
  • Joint or muscle pain
  • Signs of infection like a sore throat, cough, and fever
  • Signs of lactic acidosis (too much lactic acid in the blood) like feeling cold, fast breathing, abnormal heartbeat, and muscle pain or cramps
  • Signs of high blood sugar like confusion, excessive thirst, and breath that smells like fruit
  • Fat redistribution, including Cushingoid appearance, central obesity, facial wasting, peripheral wasting, buffalo hump, or breast enlargement
  • Signs of kidney problems like excessive weight gain, a change in how much urine is passed, and blood in the urine
  • Signs of liver problems like upset stomach or stomach pain, light-colored stools, and yellow skin or eyes (jaundice)
  • Signs of an allergic reaction can include hives, wheezing, and trouble breathing, talking, or swallowing 
  • Severe skin reaction (Stevens-Johnson syndrome/toxic epidermal necrolysis
  • Immune reconstitution syndrome
  • Decrease in bone mineral density

Report Side Effects

Symtuza may cause other side effects. Call your healthcare provider if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your healthcare provider may send a report to the FDA's MedWatch Adverse Event Reporting Program or by phone (800-332-1088).

Dosage: How Much of Symtuza Should I Take?

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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 oral dosage form (tablets):
    • For treatment of HIV infection:
      • Adults and children weighing at least 40 kilograms (kg)—1 tablet once a day with food. Each tablet contains 800 milligrams (mg) of darunavir, 150 mg of cobicistat, 200 mg of emtricitabine, and 10 mg of tenofovir alafenamide.
      • Children weighing less than 40 kilograms—Use and dose must be determined by your doctor.


Symtuza is not recommended in people with severe kidney disease. During dialysis, 30% to 54% of this medicine is removed from your system within a three-hour period. It is best to take your medicine after dialysis.

This medication is not recommended for use during pregnancy. This is because darunavir and cobicistat, two components of Symtuza, are substantially less effective in pregnant people. If you become pregnant while on this drug, your healthcare provider may consider switching you to an alternative treatment.

Missed Dose

Try not to miss or skip a dose while taking this drug. However, if you do, take the missed dose as soon as you remember. Skip the missed dose if it is too close to your next dose and return to your regular dosing schedule. Do not take extra doses or two doses at a time.

Stopping Symtuza suddenly can cause hepatitis B flare-ups in people who are already infected. Call your healthcare provider if you miss a dose and are unsure what to do.

Overdose: What Happens If I Use Too Much Symtuza?

Human data on Symtuza overdoses are limited. If you have taken too much Symtuza, immediately contact your healthcare provider or the Poison Control Center for the next steps. You may need to receive supportive treatment.

What Happens If I Overdose on Symtuza?

If you think you or someone else may have overdosed on Symtuza, call a healthcare provider or the Poison Control Center (800-222-1222).

If someone collapses or isn't breathing after taking Symtuza, call 911 immediately.


Drug Content Provided by IBM Micromedex®

It is very important that your doctor check your progress at regular visits, especially during the first few weeks that you take this medicine, to make sure this medicine is working properly. Blood and urine tests may be needed to check for any unwanted effects.

This medicine should not be used together with alfuzosin (Uroxatral®), carbamazepine (Tegretol®), dronedarone (Multaq®), elbasvir/grazoprevir (Zepatier®), ivabradine (Corlaonor®), lomitapide (Juxtapid®), lovastatin (Mevacor®), lurasidone (Latuda®), midazolam (Versed®), naloxegol (Movantik®, Moventig®), phenobarbital (Luminal®), phenytoin (Dilantin®), pimozide (Orap®), ranolazine (Ranexa®), rifampin (Rifadin®, Rimactane®), sildenafil (Revatio®), simvastatin (Zocor®), St. John's wort, triazolam (Halcion®), or ergot medicines (eg, dihydroergotamine, ergotamine, methylergonovine, Cafergot®, Ergomar®, Wigraine®). Do not use this medicine together with colchicine (Colcrys®) if you have kidney or liver disease.

Using this medicine while you are pregnant can harm your unborn baby. Birth control pills may not work as well to prevent pregnancy when used with this medicine. Use another form of birth control (eg, condoms, spermicide) along with your pills to keep from getting pregnant during treatment with this medicine. If you think you have become pregnant while using this medicine, tell your doctor right away.

Serious skin reactions (eg, Stevens-Johnson syndrome) can occur with this medicine. Check with your doctor right away if you have blistering, peeling, or loosening of the skin, chills, cough, diarrhea, itching, joint or muscle pain, red irritated eyes, red skin lesions, often with a purple center, skin rash, sore throat, sores, ulcers, or white spots in the mouth or on the lips, or unusual tiredness or weakness.

Your immune system may get stronger when you start taking 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.

A decrease in frequency or amount of urine, an increase in blood pressure, increased thirst, loss of appetite, lower back or side pain, nausea, swelling of the face, fingers, or lower legs, trouble breathing, unusual tiredness or weakness, vomiting, or weight gain. These could be symptoms of a serious kidney problem.

Two rare but serious reactions to this medicine are lactic acidosis (too much acid in the blood) and liver toxicity. These reactions are more common if you are female, obese, or have been taking anti-HIV medicines for a long time. Call your doctor right away if you have nausea, vomiting, decreased appetite, muscle cramping or pain, stomach pain, unusual tiredness or weakness, trouble breathing, or yellow skin or eyes.

This medicine may increase blood sugar levels. Check with your doctor if you notice a change in the results of your blood or urine sugar tests.

This medicine may cause you to have excess body fat. Tell your doctor if you notice changes in your body shape, such as an increased amount of fat in the upper back and neck, or around the chest and stomach area. You might also lose fat from the legs, arms, and face.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or non-prescription (over-the-counter [OTC]) medicines and herbal (eg, St John's wort) or vitamin supplements.

What Are Reasons I Shouldn't Take Symtuza?

Do not take Symtuza if you are hypersensitive to darunavir, cobicistat, emtricitabine, and tenofovir alafenamide, or any part of its formulation.

Do not take this drug if you are using certain substances, including but not limited to:

What Other Medications Interact With Symtuza?

Certain medications may alter the effects of either darunavir, cobicistat, emtricitabine, or tenofovir alafenamide or vice versa. These drugs include:

Symtuza also interacts with:

  • St. John's wort
  • Red yeast rice
  • Garlic

Additionally, since Symtuza is a complete treatment regimen for HIV, it is not recommended to take other antiretroviral medications simultaneously.

This is not a complete list of drug interactions. Talk to your healthcare provider before starting any new medication, including over-the-counter (OTC) medicines, vitamins, and herbal supplements.

What Medications Are Similar?

Medications similar to Symtuza that may be used to treat HIV infection include:

This is a list of drugs also prescribed to treat HIV infection. It is NOT a list of medicines recommended to take with Symtuza. Do not take these drugs together unless instructed by your healthcare provider.

Frequently Asked Questions

  • What is Symtuza used to treat?

    Symtuza treats HIV infection in people 3 years and older who weigh at least 40 kilograms (about 88 pounds).

  • What are the most common side effects of Symtuza?

    Some common side effects associated with Symtuza include diarrhea, gas, headache, tiredness, weakness, and upset stomach.

  • What should I do if I miss a dose of Symtuza?

    If you miss a dose of Symtuza, take it as soon as you remember, unless it is too close to your next dose. Then, skip the missed dose and return to your regular schedule. Do not double up on doses. People who have hepatitis B virus can experience a flare-up of their condition after stopping Symtuza.

How Can I Stay Healthy While Taking Symtuza?

Staying healthy is possible while living with HIV. Symtuza reduces the amount of HIV in your body; however, you must keep taking it as directed for it to continue working. Do not stop this medication suddenly without consulting your healthcare provider.

Although Symtuza helps lower viral levels in the body, it does not stop the spread of HIV entirely. Continue to take precautions to prevent transmission, including safer sex practices and not sharing needles, razors, or anything that may expose someone to bodily fluids.

Medical Disclaimer

Verywell Health's drug information is meant for educational purposes only and is not intended to replace medical advice, diagnosis, or treatment from a healthcare provider. Consult your healthcare provider before taking any new medication(s). IBM Watson Micromedex provides some of the drug content, as indicated on the page.

9 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Janssen. Symtuza label.

  2. National Library of Medicine's National Center for Biotechnology Information. Darunavir.

  3. MedlinePlus. Darunavir.

  4. Gilead. Tybost label.

  5. Gilead. Vemlidy label.

  6. National Library of Medicine's National Center for Biotechnology Information. Emtricitabine.

  7. Huhn GD, Crofoot G, Ramgopal M, et al. Darunavir/cobicistat/emtricitabine/tenofovir alafenamide in a rapid-initiation model of care for human immunodeficiency virus type 1 infection: primary analysis of the DIAMOND study. Clin Infect Dis. 2020;71(12):3110-3117. doi:10.1093/cid/ciz1213

  8. Centers for Disease Control and Prevention. HIV treatment as prevention.

  9. Centers for Disease Control and Prevention. Ways HIV can be transmitted.

By Queen Buyalos, PharmD
Queen Buyalos is a pharmacist and freelance medical writer. She takes pride in advocating for cancer prevention, overall health, and mental health education. Queen enjoys counseling and educating patients about drug therapy and translating complex ideas into simple language.