Atazanavir is an antiviral medicine that prevents human immunodeficiency virus (HIV) from multiplying in your body.

Atazanavir is used with other medications to treat HIV, the virus that can cause acquired immunodeficiency syndrome (AIDS). Atazanavir is not a cure for HIV or AIDS.

Atazanavir is for use in adults and children who are at least 3 months old and weigh at least 11 pounds (5 kilograms).

Atazanavir may also be used for purposes not listed in this medication guide.

Tell your doctor about all your current medicines and any you start or stop using. Many drugs can interact with atazanavir, and some drugs should not be used together.

Atazanavir comes as a capsule and as a powder to take by mouth. Atazanavir capsules are taken with food once a day and may be given with a pharmacokinetic booster (medication given to increase the levels of another drug in the body) such as ritonavir or cobicistat. Atazanavir powder must be taken with food and ritonavir. Take atazanavir 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 exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

You will take other medications for HIV while you are taking atazanavir. Your doctor will tell you whether these medications should be taken at the same time as atazanavir, or several hours before or after you take atazanavir. Follow this schedule carefully, and ask your doctor or pharmacist if you have questions about the times you should take your medications.

Swallow the capsules whole; do not split, chew, or open them. If you are unable to swallow the capsules, tell your doctor or pharmacist.

Atazanavir powder may be added to foods such as applesauce or yogurt, or liquids such as water, milk, or infant formula. Mix well, and take all of the mixture right away in order to take the full dose. If mixed with water, eat a snack or meal right away after taking the powder mixture. For infants (older than 3 months of age) unable to drink from a cup, the powder can be mixed with infant formula and given with an oral dosing syringe; do not give the mixture to the infant in a baby bottle. If the mixture is not taken immediately it must be stored at room temperature and taken within 1 hour. Carefully read the manufacturer's instructions that describe how to mix and take a dose of atazanavir. Be sure to ask your pharmacist or doctor if you have any questions about how to mix or take this medication.

Talk to the doctor about what to do if your baby vomits, spits up, or only takes part of the dose of atazanavir.

Atazanavir controls HIV but does not cure it. Atazanavir does not treat HIV infection alone and must always be given with 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 even if you feel well. Do not stop taking atazanavir without talking to your doctor. When your supply of atazanavir starts to run low, get more from your doctor or pharmacist. If you stop taking atazanavir or skip doses, your condition may become more difficult to treat.

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.

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Atazanavir must be given in combination with other antiviral medications and should not be used alone.

Take atazanavir with food. Swallow the capsule whole and do not crush, chew, break, or open it.

Drink extra fluids to keep your kidneys working properly while using this medicine.

Read and carefully follow any Instructions for Use provided with your medicine. Ask your doctor or pharmacist if you do not understand these instructions.

Atazanavir powder must be mixed with a food or liquid, and taken within 1 hour of mixing. Give the ritonavir dose to your child immediately after giving the atazanavir mixture.

Your dose needs may change if you switch to a different brand, strength, or form of this medicine. Avoid medication errors by using only the form and strength your doctor prescribes.

Atazanavir doses are based on weight in children. Your child's dose needs may change if the child gains or loses weight.

You will need frequent medical tests.

Use all HIV medications as directed and read all medication guides you receive. Do not change your dose or stop using a medicine without your doctor's advice. Every person with HIV should remain under the care of a doctor.

Store at room temperature away from moisture and heat. Keep the powder in the original packet until you are ready to mix a dose.

After mixing the powder with food or liquid, keep the mixture at room temperature and use it within 1 hour.

You should not use atazanavir if you have ever had a severe allergic reaction to atazanavir.

Some medicines can cause unwanted or dangerous effects when used with atazanavir. Your doctor may need to change your treatment plan if you use:

• alfuzosin;

• cisapride;

• irinotecan;

• rifampin;

• sildenafil (Revatio, for treating pulmonary arterial hypertension);

• St. John's wort;

• antipsychotic medicine--lurasidone, pimozide;

• antiviral medicine--elbasvir/grazoprevir, glecaprevir/pibrentasvir, indinavir, nevirapine;

• ergot medicines--dihydroergotamine, ergotamine, ergonovine, methylergonovine;

• heart rhythm medication--amiodarone, quinidine;

• medicine to lower cholesterol--lomitapide, lovastatin, simvastatin; or

• sedative medicines--triazolam, oral midazolam.

Tell your doctor if you have ever had:

• liver disease (especially hepatitis B or C);

• kidney disease (or if you are on dialysis);

• kidney stones or gallstones;

• diabetes;

• a bleeding disorder such as hemophilia; or

• heart problems.

Atazanavir oral powder may contain phenylalanine. Tell your doctor if you have phenylketonuria (PKU).

Atazanavir can make hormonal birth control less effective, including birth control pills, injections, implants, skin patches, and vaginal rings. To prevent pregnancy while using atazanavir, use a barrier form of birth control: condom, diaphragm, cervical cap, or contraceptive sponge.

Tell your doctor if you are pregnant, and use your medications properly to control your infection. HIV can be passed to your baby if the virus is not controlled during pregnancy. Your dose needs may be different during pregnancy and for a short time after childbirth.

If you are pregnant, your name may be listed on a registry to track the effects of atazanavir on the baby. If you took atazanavir during pregnancy, tell your doctor if your newborn baby has a yellow appearance in the skin or the whites of the eyes.

Women with HIV or AIDS should not breastfeed a baby. Even if your baby is born without HIV, the virus may be passed to the baby in your breast milk.

Atazanavir should not be given to a child younger than 3 months old and weighing less than 11 pounds (5 kilograms).

Take the medicine as soon as you remember, and then go back to your regular schedule. Do not take two doses at one time.

Get your prescription refilled before you run out of medicine completely.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

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

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

Talk to your doctor about eating grapefruit or drinking grapefruit juice while taking this medicine.

Using atazanavir may not prevent your disease from spreading. Do not have unprotected sex or share razors or toothbrushes. Talk with your doctor about safe ways to prevent HIV transmission during sex. Sharing drug or medicine needles is never safe, even for a healthy person.

Get emergency medical help if you have signs of an allergic reaction (hives, difficult breathing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning in your eyes, skin pain, red or purple skin rash that spreads and causes blistering and peeling).

Atazanavir may cause serious side effects. Call your doctor at once if you have:

• sudden dizziness (like you might pass out);

• severe pain in your lower stomach or back;

• painful urination, blood in your urine;

• high blood sugar--increased thirst, increased urination, dry mouth, fruity breath odor, headache, blurred vision; or

• liver or gallbladder problems--nausea, vomiting, upper stomach pain, itching, fever, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Atazanavir affects your immune system, which may cause certain side effects (even weeks or months after you've taken atazanavir). Tell your doctor if you have:

• signs of a new infection--fever, night sweats, swollen glands, cold sores, cough, wheezing, diarrhea, weight loss;

• trouble speaking or swallowing, problems with balance or eye movement;

• weakness or prickly feeling, loss of bladder or bowel control; or

• swelling in your neck or throat (enlarged thyroid), menstrual changes, impotence.

Common side effects of atazanavir may include:

• fever;

• nausea, vomiting, stomach pain, diarrhea;

• headache, muscle pain;

• depressed mood, sleep problems (insomnia);

• numbness, tingling, or burning pain in your hands or feet; or

• changes in the shape or location of body fat (especially in your arms, legs, face, neck, breasts, and waist).

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Sometimes it is not safe to use certain medications at the same time. Some drugs can affect your blood levels of other drugs you take, which may increase side effects or make the medications less effective.

Many drugs can affect atazanavir. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here. Tell your doctor about all your current medicines and any medicine you start or stop using.

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

Keep a supply of atazanavir 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.