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Atazanavir and Cobicistat

pronounced as (at a za na' veer) (koe bik' i stat)

Why is this medication prescribed?

The combination of atazanavir and cobicistat, along with other medications, is used to treat human immunodeficiency virus (HIV) infection in adults and children who weigh at least 77 lb (35 kg). Atazanavir is in a class of medications called protease inhibitors. It works by decreasing the amount of HIV in the blood. Cobicistat is in a class of medications called pharmacokinetic boosters. It works by increasing the amount of atazanavir in the body so that it can have a greater effect. Although atazanavir 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 the HIV virus to other people.

How should this medicine be used?

Atazanavir and cobicistat comes as a tablet to take by mouth. It is usually taken with food one time a day. Take atazanavir and cobicistat at around the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take atazanavir and cobicistat exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the tablets whole; do not split, chew, or crush them.

Atazanavir and cobicistat controls HIV but does not cure it. Atazanavir and cobicistat does not treat HIV infection alone and must always be given as part of a complete regimen. It is important that all of the medications prescribed by your doctor to treat HIV infection are taken together so that the medications will continue to work to control the infection. Continue to take atazanavir and cobicistat even if you feel well. Do not stop taking atazanavir and cobicistat without talking to your doctor.

Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient. Read this information carefully and ask your doctor or pharmacist if you have any questions.

Other uses for this medicine

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

What special precautions should I follow?

Before taking atazanavir and cobicistat,

  • tell your doctor and pharmacist if you are allergic to atazanavir or cobicistat, any other medications, or any of the ingredients in atazanavir and cobicistat tablets. Ask your pharmacist for a list of the ingredients.
  • Some medications should not be taken with atazanavir and cobicistat. Other medications may cause dosing changes or extra monitoring when taken with atazanavir and cobicistat. Make sure you have discussed any medications you are currently taking or plan to take before starting atazanavir and cobicistat with your doctor and pharmacist. Before starting, stopping, or changing any medications while taking atazanavir and cobicistat, please get the advice of your doctor or pharmacist.
  • The following nonprescription or herbal products may interact with atazanavir: medications for indigestion, heartburn or ulcers (esomeprazole (Nexium), famotidine (Pepcid), omeprazole (Prilosec, Zegerid), ranitidine (Zantac)) or St. John's wort. Be sure to let your doctor and pharmacist know that you are taking these medications before you start taking atazanavir and cobicistat. Do not start any of these medications while taking atazanavir and cobicistat without discussing with your healthcare provider.
  • if you are taking antacids or any other buffered medication such as buffered aspirin (Bufferin), take atazanavir and cobicistat 2 hours before or 2 hours after you take the medication. If you are taking didanosine delayed-release capsules (Videx EC), take atazanavir and cobicistat 2 hours before or 1 hour after you take the medication. Ask your doctor or pharmacist if you are not sure if any of the medications you are taking are buffered.
  • tell your doctor if you have or have ever had an irregular heartbeat, diabetes or high blood sugar, hemophilia (a condition in which the blood does not clot normally) or any other bleeding disorder, hepatitis (a viral infection of the liver) or any other liver disease, kidney or heart disease.
  • tell your doctor if you are pregnant or plan to become pregnant. If you become pregnant while taking atazanavir and cobicistat, call your doctor. You should not breast-feed if you are infected with HIV and are taking atazanavir and cobicistat.
  • you should know that atazanavir and cobicistat may decrease the effectiveness of hormonal contraceptives (birth control pills, patches, rings, implants, and injections). Talk to your doctor about methods of birth control that will work for you while you are taking atazanavir and cobicistat.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking atazanavir and cobicistat.
  • you should know that you may experience hyperglycemia (increases in your blood sugar) while you are taking this medication, even if you do not already have diabetes. Tell your doctor immediately if you have any of the following symptoms while you are taking atazanavir and cobicistat: extreme thirst, frequent urination, extreme hunger, blurred vision, or weakness. It is very important to call your doctor as soon as you have any of these symptoms, because high blood sugar that is not treated can cause a serious condition called ketoacidosis. Ketoacidosis may become life-threatening if it is not treated at an early stage. Symptoms of ketoacidosis include: dry mouth, nausea and vomiting, shortness of breath, breath that smells fruity, and decreased consciousness.
  • you should know that while you are taking medications to treat HIV infection, your immune system may get stronger and begin to fight other infections that were already in your body. This may cause you to develop symptoms of those infections. If you have new or worsening symptoms at any time during your treatment with atazanavir and cobicistat, be sure to tell your doctor.
  • you should know that your body fat may increase or move to different areas of your body such as your breasts, upper back, neck, chest, and stomach area. Loss of fat from the legs, arms, and face can also happen.

What special dietary instructions should I follow?

Talk to your doctor about eating grapefruit and drinking grapefruit juice while taking this medication.

What should I do if I forget a dose?

Take 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 take a double dose to make up for a missed one..

What side effects can this medication cause?

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

  • yellowing of the skin or eyes
  • rash
  • nausea
  • diarrhea
  • headache

Some side effects can be serious. If you experience any of the following symptoms, call your doctor immediately or get emergency medical treatment:

  • irregular heartbeat
  • dizziness
  • feeling faint or lightheadedness
  • vision changes
  • yellowing of skin or eyes (especially in newborn infants)
  • pain in your back or low stomach area
  • pain with urination
  • blood in urine
  • vomiting
  • loss of appetite
  • decreased urination
  • dark-colored urine
  • light-colored bowel movements

If you develop a severe rash with any of the following symptoms, stop taking atazanavir and cobicistat and call your doctor immediately or get emergency medical treatment:

  • general ill feeling or 'flu-like' symptoms
  • fever
  • muscle or joint aches
  • red or swollen eyes
  • blisters or peeling skin
  • mouth sores
  • swelling of your face or neck
  • painful, warm, or red lump under your skin

Atazanavir and cobicistat may cause other side effects. Call your doctor if you have any unusual problems while taking 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 ( or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

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.

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 ( for more information if you do not have access to a take-back program.

In case of emergency/overdose

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

Symptoms of overdose may include:

  • yellowing of skin or eyes
  • changes in heart rhythm or irregular heartbeat

What other information should I know?

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

Keep a supply of atazanavir and cobicistat on hand. Do not wait until you run out of medication to refill your prescription.

Do not let anyone else take 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.

Brand names

  • Evotaz®
Last Revised - 09/15/2023