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Generic Name: atazanavir (a ta ZAN a vir)
Brand Name: Reyataz

What is atazanavir?

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

Atazanavir is used with other medications to treat HIV, which causes the acquired immunodeficiency syndrome (AIDS). Atazanavir is not a cure for HIV or AIDS.

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

What is the most important information I should know about 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 any of the following drugs: alfuzosin, cisapride, indinavir, irinotecan, lovastatin, simvastatin, pimozide, rifampin, sildenafil (for treating pulmonary arterial hypertension), St. John's wort, triazolam, oral midazolam, or ergot medicine (dihydroergotamine, ergotamine, ergonovine, methylergonovine).

What should I discuss with my healthcare provider before taking atazanavir?

You should not use this medicine 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 any of the following drugs:

  • alfuzosin;

  • cisapride;

  • indinavir;

  • irinotecan;

  • lovastatin, simvastatin;

  • pimozide;

  • rifampin;

  • sildenafil (for treating pulmonary arterial hypertension);

  • St. John's wort;

  • triazolam, oral midazolam; or

  • ergot medicine--dihydroergotamine, ergotamine, ergonovine, methylergonovine.

To make sure atazanavir is safe for you, tell your doctor if you have:

  • liver disease, hepatitis B or C;

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

  • history of kidney stones or gallstones;

  • diabetes;

  • a bleeding disorder such as hemophilia;

  • high cholesterol or triglycerides;

  • a heart rhythm disorder, a heart condition called "AV block"; or

  • if you have ever used a protease inhibitor in the past.

Atazanavir is not expected to be harmful to an unborn baby, but HIV can be passed to your baby if you are not properly treated during pregnancy. Take all of your HIV medicines as directed to control your infection. Atazanavir must be given together with ritonavir during pregnancy and for a short time after childbirth. Follow your doctor's dosing instructions very carefully.

Atazanavir can make birth control pills, patches, injections, or vaginal rings less effective. Ask your doctor about using a non-hormone method of birth control (such as a condom, diaphragm, spermicide) to prevent pregnancy while taking atazanavir.

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

Do not give this medication to a child younger than 6 years old. Do not give atazanavir alone (without ritonavir) to a child younger than 13 years old, or to a child who weighs less than 88 pounds.

How should I take atazanavir?

Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended. Atazanavir is often used together with another medicine called ritonavir (Norvir).

Atazanavir should be taken once daily with food. Swallow the capsule whole.

While using atazanavir, you may need frequent blood tests at your doctor's office. Your liver function may also need to be checked.

Use atazanavir regularly to get the most benefit. Get your prescription refilled before you run out of medicine completely.

HIV/AIDS is usually treated with a combination of drugs. Use all medications as directed by your doctor. Read the medication guide or patient instructions provided with each medication. Do not change your doses or medication schedule without your doctor's advice. Every person with HIV or AIDS should remain under the care of a doctor.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if your next dose is less than 6 hours away. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

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

What should I avoid while taking atazanavir?

If you also take didanosine (Videx), take it 1 hour before or 2 hours after you take atazanavir. Avoid using antacids or buffered aspirin within 1 hour before or 2 hours after you take atazanavir.

Taking this medicine will not prevent you from passing HIV to other people. 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.

Atazanavir side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Atazanavir may increase your risk of certain infections or autoimmune disorders by changing the way your immune system works. Symptoms may occur weeks or months after you start treatment with atazanavir. Tell your doctor if you have:

  • signs of a new infection--fever, night sweats, swollen glands, diarrhea, stomach pain, weight loss;

  • chest pain (especially when you breathe), dry cough, wheezing, feeling short of breath;

  • cold sores, sores on your genital or anal area;

  • rapid heart rate, feeling anxious or irritable, weakness or prickly feeling, problems with balance or eye movement;

  • trouble speaking or swallowing, severe lower back pain, loss of bladder or bowel control; or

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

Stop taking atazanavir and call your doctor at once if you have:

  • headache with chest pain and severe dizziness, fainting, fast or pounding heartbeats;

  • severe pain in your side or lower back, painful urination, blood in your urine;

  • jaundice (yellowing of the skin or eyes);

  • high blood sugar (increased thirst, increased urination, hunger, dry mouth, fruity breath odor, drowsiness, dry skin, blurred vision); or

  • severe skin reaction -- fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain, followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.

Common side effects may include:

  • nausea, vomiting, stomach pain;

  • muscle pain, mild itching or rash;

  • headache, dizziness, depressed mood, sleep problems (insomnia);

  • numbness 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.

See also: Side effects (in more detail)

Atazanavir dosing information

Usual Adult Dose for HIV Infection:

-Recommended dose: Atazanavir 300 mg plus ritonavir 100 mg orally once a day
-If unable to tolerate ritonavir: 400 mg orally once a day
-If used with efavirenz: Atazanavir 400 mg plus ritonavir 100 mg orally once a day

-Recommended dose: Atazanavir 300 mg plus ritonavir 100 mg orally once a day
-If used with both an H2-receptor antagonist and tenofovir: Atazanavir 400 mg plus ritonavir 100 mg orally once a day

Therapy-naive and Therapy-experienced Patients:
-Recommended dose: Atazanavir 300 mg plus ritonavir 100 mg orally once a day

Therapy-experienced Patients during the Second or Third Trimester:
-If used with either an H2-receptor antagonist or tenofovir: Atazanavir 400 mg plus ritonavir 100 mg orally once a day
-If used with both an H2-receptor antagonist and tenofovir: Not recommended.

-This drug must be used with ritonavir during pregnancy.
-This drug should only be used in pregnant women with HIV-1 strains susceptible to atazanavir.
-No dose adjustment needed for pregnant patients with the above exceptions.
-No dose adjustment needed for postpartum patients; close monitoring for side effects recommended (higher drug exposures possible during first 2 months after delivery).

Use: In combination with other antiretroviral agents, for the treatment of HIV-1 infection

Usual Adult Dose for Nonoccupational Exposure:

US CDC recommendations:
-Recommended dose: 400 mg orally once a day
-If used with tenofovir: Atazanavir 300 mg plus ritonavir 100 mg orally once a day

Duration of therapy: 28 days

-Recommended as an alternative regimen for nonoccupational postexposure prophylaxis of HIV infection
-This drug should be used with (lamivudine or emtricitabine) plus (zidovudine or stavudine or abacavir or didanosine) or (tenofovir plus ritonavir [100 mg/day]).
-Prophylaxis should be started as soon as possible, within 72 hours of exposure.
-Not approved by US FDA.

Usual Pediatric Dose for HIV Infection:

Therapy-naive and Therapy-experienced Patients:
3 months or older:
10 to less than 15 kg: Atazanavir 200 mg plus ritonavir 80 mg orally once a day
15 to less than 25 kg: Atazanavir 250 mg plus ritonavir 80 mg orally once a day

Therapy-naive and Therapy-experienced Patients:
6 to less than 18 years:
15 to less than 20 kg: Atazanavir 150 mg plus ritonavir 100 mg orally once a day
20 to less than 40 kg: Atazanavir 200 mg plus ritonavir 100 mg orally once a day
40 or more: Atazanavir 300 mg plus ritonavir 100 mg orally once a day

Therapy-naive Patients Unable to Tolerate Ritonavir:
13 to less than 18 years:
40 kg or more: 400 mg orally once a day

-Each packet of the oral powder contains 50 mg of atazanavir.
-The oral powder should be administered after mixing with food or beverage; ritonavir should be administered immediately after that.
-The oral powder is not recommended for patients weighing less than 10 kg or 25 kg or more.
-The capsules and ritonavir should be administered simultaneously with food.
-The capsules must be used with ritonavir in therapy-experienced patients.
-According to the Panel on Antiretroviral Therapy and Medical Management of HIV-infected Children, some experts recommend increasing atazanavir to 300 mg at a weight of at least 35 kg to avoid underdosing, especially when tenofovir is coadministered.

Use: In combination with other antiretroviral agents, for the treatment of HIV-1 infection

What other drugs will affect atazanavir?

Many drugs can interact with atazanavir. Not all possible interactions are listed here. Tell your doctor about all your medications and any you start or stop using during treatment with atazanavir, especially:

  • bosentan;

  • buprenorphine;

  • colchicine;

  • fluticasone (especially if you also take ritonavir);

  • paclitaxel;

  • quetiapine;

  • repaglinide;

  • salmeterol (with or without fluticasone);

  • warfarin (Coumadin);

  • other HIV/AIDS medications;

  • the hepatitis C medications boceprevir or telaprevir;

  • an antibiotic--clarithromycin, rifabutin;

  • an antidepressant--amitriptyline, doxepin, desipramine, imipramine, protriptyline, trazodone, trimipramine;

  • antifungal medicine--ketoconazole, itraconazole, voriconazole;

  • cholesterol-lowering medications--atorvastatin, rosuvastatin;

  • drugs to prevent organ transplant rejection--cyclosporine, sirolimus, tacrolimus;

  • erectile dysfunction medications--avanafil, sildenafil, tadalafil, vardenafil;

  • heart or blood pressure medication--amiodarone, diltiazem, felodipine, lidocaine, nicardipine, nifedipine, quinidine, verapamil;

  • seizure medication--carbamazepine, fosphenytoin, lamotrigine, oxcarbazepine, phenobarbital, phenytoin, primidone; or

  • stomach acid reducers--cimetidine, dexlansoprazole, esomeprazole, famotidine, lansoprazole, nizatidine, omeprazole, pantoprazole, ranitidine, and others.

This list is not complete and many other drugs can interact with atazanavir. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Give a list of all your medicines to any healthcare provider who treats you.

Where can I get more information?

  • Your pharmacist can provide more information about atazanavir.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2012 Cerner Multum, Inc. Version: 9.03.

Last reviewed: April 28, 2015
Date modified: July 02, 2017