Some drugs should not be taken with cobicistat. Cobicistat may interact with many drugs, which can cause serious, life-threatening side effects.
When taken with certain other medicines, cobicistat can cause new or worse kidney problems, including kidney failure. Your health care provider should check your kidneys before you start and while you are taking cobicistat.
If you are taking cobicistat, tell your health care provider about other prescription and nonprescription medicines, vitamins, nutritional supplements, and herbal products (including St. John's Wort) you are taking or plan to take.
While taking cobicistat, it is important to keep all of your appointments with your health care provider.
Cobicistat is a prescription medicine approved by the U.S. Food and Drug Administration (FDA) for use in adults one time each day with the HIV medicines atazanavir (brand name: Reyataz) or darunavir (brand name: Prezista) to increase the amount of those medicines in the blood.
Cobicistat is a type of medicine called a pharmacokinetic enhancer. Pharmacokinetic enhancers are used in HIV treatment to increase the amount of other HIV medicines in the blood. When used with atazanavir or darunavir, cobicistat interferes with the breakdown of the drugs in the body. In this way, cobicistat increases the blood levels of atazanavir or darunavir, making them more effective.
Cobicistat is not an HIV medicine and does not treat HIV. Even if you take cobicistat and atazanavir or darunavir, you must also take all the HIV medicines prescribed by your health care provider. Do not cut down on, skip, or stop taking cobicistat or any HIV medicines unless your health care provider tells you to.
Before taking cobicistat, tell your health care provider:
Cobicistat (brand name: Tybost) comes in tablet form. Each tablet contains 150 mg of cobicistat.
Take cobicistat according to your health care provider’s instructions.
Take cobicistat one time each day at the same time you take atazanavir (brand name: Reyataz) or darunavir (brand name: Prezista). It is important to take these medicines on a regular dosing schedule.
Take cobicistat with food.
If you take too much cobicistat, contact your health care provider or local poison control center (1-800-222-1222) right away, or go to the nearest hospital emergency room.
For more information on how to take cobicistat, see the FDA drug label from DailyMed. (DailyMed is a federal website that includes the most recent drug labels submitted to FDA.)
If you miss a dose of cobicistat with atazanavir (brand name: Reyataz) or darunavir (brand name: Prezista) by less than 12 hours, take the missed dose of cobicistat with atazanavir or darunavir right away. Then take your next dose of cobicistat together with atazanavir or darunavir as usual. If you miss a dose of cobicistat with atazanavir or darunavir by more than 12 hours, wait and take the next dose at your usual time. If you miss a dose of cobicistat with atazanavir or darunavir, do not take two doses at the same time to make up for the missed dose.
Cobicistat may cause side effects. Most side effects from cobicistat are manageable, but a few can be serious. Some drugs should not be taken with cobicistat. Cobicistat may interact with many drugs, which can cause serious, life-threatening side effects. When taken with certain other medicines, cobicistat can cause new or worse kidney problems, including kidney failure. (See the WARNING above.)
Tell your health care provider if you have any side effect that bothers you or that does not go away.
These are not all the possible side effects of cobicistat. To learn more about possible side effects of cobicistat, read the drug label or package insert or talk to your health care provider or pharmacist.
The AIDSinfo fact sheet on HIV Medicines and Side Effects also includes information that may apply to cobicistat.
You can also report side effects to FDA at 1-800-FDA-1088 (1-800-332-1088) or online at https://www.accessdata.fda.gov/scripts/medwatch/.
More information about cobicistat is available:
Gilead Sciences, Inc.
Main number: 800-445-3235
Patient assistance: 800-226-2056
Last Reviewed: July 11, 2016