Cobicistat

WHY is this medicine prescribed?

Cobicistat is used to increase the amounts of atazanavir or darunavir when these medications are used to treat human immunodeficiency virus (HIV). Cobicistat is in a class of medications called pharmacokinetic boosters. It works by increasing the amount of atazanavir or darunavir in the body so that they can have a greater effect.

Are there OTHER USES for this medicine?

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

HOW should this medicine be used?

Cobicistat comes as a tablet to take by mouth. Take with food once a day along with atazanavir or darunavir. Always take cobicistat at the same time as atazanavir or darunavir at around the same time every day.

Take cobicistat exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.

What SPECIAL PRECAUTIONS should I follow?

Before taking cobicistat,

• tell your doctor or pharmacist if you are allergic to this drug, any part of this drug, or any otherdrugs, foods or substances. Tell your doctor or pharmacist about the allergy and whatsymptoms you had.

• some medications should not be taken with cobicistat. Other medications may cause dosing changes or extra monitoring when taken with cobicistat. Make sure you have discussed any medications you are currently taking or plan to take before starting cobicistat with your doctor and pharmacist. Before starting, stopping, or changing any medications while taking cobicistat, please get the advice of your doctor or pharmacist.

• the following herbal product may interact with cobicistat: St. John's wort. Be sure to let your doctor and pharmacist know that you are taking this medication before you start taking cobicistat. Do not start this medication while taking cobicistat without discussing with your healthcare provider.

• if you are taking cobicistat with atazanavir and you are also taking antacids (Maalox^®, Mylanta^®, Tums^®, others), take them 2 hours before or 2 hours after cobicistat and atazanavir.

• if you are taking cobicistat with atazanavir and you are also taking a medication for indigestion, heartburn, or ulcers (H2 blockers) such as cimetidine, famotidine, nizatidine, or ranitidine, take them at the same time or at least 10 hours after taking the H2 blocker.

• if you are taking cobicistat with atazanavir and you are also taking a medication for indigestion, heartburn, or ulcers (proton pump inhibitors) such as esomeprazole, lansoprazole, omeprazole, pantoprazole, or rabeprazole, take them at least 12 hours after taking the proton pump inhibitor.

• you should know that cobicistat may decrease the effectiveness of hormonal contraceptives (birth control pills, patches, rings, and injections). You will need to use another method of contraception to prevent pregnancy while taking cobicistat. Talk to your doctor about other ways to prevent pregnancy while you are taking this medication.

• tell your doctor if you have or have ever had kidney or liver disease.

• tell your doctor if you are pregnant, or plan to become pregnant. If you become pregnant while taking cobicistat, call your doctor.

• tell your doctor if you are breastfeeding or plan to breastfeed. Some of the medication and HIV may be passed to your baby in your breast milk. Talk to your doctor about the risks of breastfeeding your baby if you are taking cobicistat.

What SPECIAL DIETARY instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do IF I FORGET to take 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.

It is important that you take cobicistat, and all other medications prescribed by your doctor to treat HIV medication, every day and on a regular schedule. Missed doses may cause the medications to not work as well at treating the infection. Do not stop any of these medications without talking to your doctor.

What SIDE EFFECTS can this medicine cause?

Cobicistat may cause side effects. Tell your doctor if this symptom is severe or does not go away:

• nausea

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately:

• yellowing of the skin or eyes
• rash
• decreased urination

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 (https://www.fda.gov/Safety/MedWatch) 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).

Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location – one that is up and away and out of their sight and reach. https://www.upandaway.org

Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website https://goo.gl/c4Rm4p for more information.

What should I do in case of OVERDOSE?

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

What OTHER INFORMATION should I know?

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 cobicistat.

Keep a supply of medication 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.

Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines, vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list with you in case of emergencies.