Cobicistat and darunavir is a combination medicine given with other medicines to treat human immunodeficiency virus (HIV) in adults, the virus that can cause acquired immunodeficiency syndrome (AIDS). cobicistat and darunavir is not a cure for HIV or AIDS.

Cobicistat and darunavir is for use in people who weigh at least 88 pounds (40 kilograms).

Cobicistat and darunavir 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, and some drugs should not be used together.

Call your doctor at once if you have signs of a serious side effect--upper stomach pain, vomiting, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes), fever, tiredness, eye redness, muscle or joint pain, skin sores, or a skin rash with blistering.

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

Take this medicine once daily with food.

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.

Store at room temperature, away from moisture and heat. Keep the bottle tightly closed when not in use.

Usual Adult Dose for HIV Infection:

1 tablet orally once a day with food

Comments:
-This drug is not recommended during pregnancy due to considerably lower exposures of darunavir and cobicistat during the second and third trimesters of pregnancy.
-This drug should not be started in pregnant patients; patients who become pregnant during therapy with this drug should be switched to an alternative regimen.

Use: In combination with other antiretroviral agents, for the treatment of HIV-1 infection in therapy-naive and therapy-experienced patients without darunavir resistance-associated substitutions (V11I, V32I, L33F, I47V, I50V, I54L, I54M, T74P, L76V, I84V, L89V)

Usual Pediatric Dose for HIV Infection:

At least 40 kg: 1 tablet orally once a day with food

Comments:
-This drug is not recommended during pregnancy due to considerably lower exposures of darunavir and cobicistat during the second and third trimesters of pregnancy.
-This drug should not be started in pregnant patients; patients who become pregnant during therapy with this drug should be switched to an alternative regimen.

Use: In combination with other antiretroviral agents, for the treatment of HIV-1 infection in therapy-naive and therapy-experienced patients without darunavir resistance-associated substitutions (V11I, V32I, L33F, I47V, I50V, I54L, I54M, T74P, L76V, I84V, L89V)

You should not take cobicistat and darunavir if you are allergic to cobicistat or darunavir.

Some medicines can cause unwanted or dangerous effects when used with cobicistat and darunavir. Your doctor may change your treatment plan if you also use:

• alfuzosin;

• cisapride;

• colchicine;

• elbasvir and grazoprevir (Zepatier);

• naloxegol;

• rifampin;

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

• St. John's wort;

• heart medication--dronedarone, ivabradine, ranolazine;

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

• antipsychotic medicine--lurasidone, pimozide;

• oral sedatives--midazolam, triazolam;

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

• seizure medicine--carbamazepine, phenobarbital, phenytoin.

Tell your doctor if you have ever had:

• liver disease (especially hepatitis B or C);

• kidney disease;

• a bleeding or blood clotting disorder such as hemophilia;

• an allergy to sulfa drugs;

• diabetes; or

• if you also take tenofovir or ritonavir.

Cobicistat and darunavir may not work as well if you take it during pregnancy. Do not start taking this medicine if you are pregnant, and tell your doctor if you become pregnant.

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.

If you do not plan to get pregnant, ask your doctor about using a non-hormonal birth control (condom, diaphragm with spermicide) to prevent pregnancy. Cobicistat and darunavir can increase certain side effects when taken with hormonal birth control (pills, injections, implants, skin patches, vaginal rings).

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.

Cobicistat and darunavir should not be given to children younger than 3 years of age, or to people who weigh less than 88 pounds (40 kilograms).

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.

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

Taking this medication 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.

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, tiredness, muscle or joint pain, blisters or skin lesions, mouth sores or ulcers, red or inflamed eyes).

Cobicistat and darunavir may cause serious side effects. Call your doctor at once if you have:

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

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

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

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

• stomach pain, tiredness, itching, skin redness, yellowing of the skin or eyes;

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

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

Common side effects of cobicistat and darunavir may include:

• nausea, vomiting, stomach pain, diarrhea;

• headache;

• rash; 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.

If you also take enteric-coated didanosine (Videx EC), take it 1 hour before or 2 hours after you take cobicistat and darunavir.

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 cobicistat and darunavir. 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.