cobicistat

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

Tell your doctor about all your current medicines and any you start or stop using. Many drugs can interact with cobicistat and cause dangerous effects that could lead to death.

What is cobicistat?

Cobicistat is given together with atazanavir (Reyataz) or darunavir (Prezista) to treat human immunodeficiency virus (HIV), the virus that can cause acquired immunodeficiency syndrome (AIDS).

Cobicistat is used to increase your blood levels of these medicines, helping to make them safer and more effective at lower doses.

Cobicistat is not an antiviral medicine and will not treat HIV or AIDS. Cobicistat is given only to help increase your blood levels of atazanavir or darunavir.

When given with atazanavir, cobicistat is for use in adults and children weighing at least 77 pounds (35 kilograms). When given with darunavir, cobicistat is for use in adults and children weighing at least 88 pounds (40 kilograms).

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

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

Cobicistat is not a complete treatment and must be used in combination only with atazanavir or darunavir. You should not take cobicistat with any other antiviral medicines that your doctor has not prescribed.

Many drugs can interact and cause dangerous effects that could lead to death. Some drugs should not be used together.

You should not take cobicistat with atazanavir if you also take:

• indinavir;
• irinotecan;
• nevirapine; or
• birth control pills that contain drospirenone and ethinyl estradiol (Beyaz, Sayfral, Yasmin, Yaz).

You should not take cobicistat with atazanavir or darunavir if you also take:

• alfuzosin;
• cisapride;
• colchicine;
• dronedarone;
• oral midazolam, or triazolam;
• ranolazine;
• rifampin;
• sildenafil (Revatio, for treating pulmonary arterial hypertension);
• St. John's wort;
• antipsychotic medicine --lurasidone, pimozide;
• cholesterol medication --lomitapide, lovastatin, simvastatin;
• ergot medicine --dihydroergotamine, ergotamine, methylergonovine; or
• seizure medication --carbamazepine, phenobarbital, phenytoin.

You may not be able to take cobicistat if you also take:

• darunavir 600 milligrams twice daily; or
• certain other antiviral medicines --fosamprenavir, saquinavir, or tipranavir.

Tell your doctor if you have ever had:

• liver disease; or
• kidney disease, especially if you also take tenofovir.

If you plan to get pregnant, ask your doctor for another antiviral medicine to use during pregnancy. Use all medications properly to control your infection. HIV can be passed to your baby if the virus is not controlled during pregnancy. Your name may be listed on a registry to track any effects of antiviral medicine on the baby.

How should I take cobicistat?

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

Cobicistat is usually taken once per day with atazanavir or darunavir.

If you take cobicistat with atazanavir and you also take medicine to reduce stomach acid, follow these recommendations unless your doctor tells you otherwise:

• If you take an antacid, take it at least 2 hours before or 2 hours after you take cobicistat and atazanavir.
• If you take a medicine such as cimetidine, ranitidine, Tagamet, Axid, Zantac, Pepcid, and others: Take the stomach medicine at the same time you take cobicistat and atazanavir; or wait at least 10 hours after taking the stomach medicine to take your cobicistat and atazanavir doses.
• If you take a proton pump inhibitor such as omeprazole, esomeprazole, Nexium, Prevacid, Prilosec, Protonix: Wait at least 12 hours after taking the stomach medicine to take your cobicistat and atazanavir doses.

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 dosing schedule without your doctor's advice. Every person with HIV should remain under the care of a doctor.

What happens if I miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

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

What happens if I overdose?

What should I avoid while taking cobicistat?

Using this medicine will 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.

What are the possible side effects of cobicistat?

• kidney problems --little or no urination, swelling in your feet or ankles, feeling tired or short of breath; or
• liver problems --upper stomach pain, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Common side effects may include:

• nausea;
• jaundice; or
• rash.

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.

What other drugs will affect cobicistat?

When you start or stop taking cobicistat, your doctor may need to adjust the doses of any other medicines you take on a regular basis.

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.

Tell your doctor about all your current antiviral medicines.

Many drugs can affect cobicistat, and some drugs should not be used at the same time. Tell your doctor about all your current medicines and any medicine you start or stop using. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here.

Where can I get more information?

Your pharmacist can provide more information about cobicistat.