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An Overview of Isentress (Raltegravir, MK-0518)

February 9, 2015

Isentress Isentress Isentress

Brand Name: Isentress
Other Name(s): RAL, raltegravir potassium
Drug Class: Integrase Inhibitors
Approved Use: Treatment of HIV Infection

Chemical Image:


raltegravir potassium
Molecular Weight: 482.511


Raltegravir can cause serious, life-threatening side effects. These include skin reactions, allergic reactions, and liver problems.

Stop taking raltegravir and contact your health care provider right away if you develop a rash with any of the following symptoms:

An allergic reaction to raltegravir can cause liver problems. Contact your health care provider right away if you have any of the following symptoms that could be signs of liver problems:

While taking raltegravir, it is important to keep all of your appointments with your health care provider.

What Is Raltegravir?

Raltegravir is a prescription medicine approved by the U.S. Food and Drug Administration (FDA) for the treatment of HIV infection in adults and children 4 weeks of age and older. Raltegravir is always used in combination with other HIV medicines.

Raltegravir belongs to a class (group) of HIV drugs called integrase inhibitors. Integrase inhibitors block an HIV enzyme called integrase. (An enzyme is a protein that starts or increases the speed of a chemical reaction.) By blocking integrase, integrase inhibitors prevent HIV from multiplying and can reduce the amount of HIV in the body.

HIV medicines can't cure HIV/AIDS, but taking a combination of HIV medicines (called an HIV regimen) every day helps people with HIV live longer, healthier lives. HIV medicines also reduce the risk of HIV transmission.

What Should I Tell My Health Care Provider Before Taking Raltegravir?

Before taking raltegravir, tell your health care provider:

How Should I Take Raltegravir?

Raltegravir comes in the following forms and strengths:

Take raltegravir according to your health care provider's instructions.

Take raltegravir by mouth, with or without food. Always swallow the film-coated tablets whole. The chewable tablets may be chewed or swallowed. Raltegravir for oral suspension must be mixed with water before use and given within 30 minutes of mixing. Raltegravir for oral suspension comes in a kit that contains the packets of raltegravir and reusable syringes and cups needed to mix and give the medicine. See the detailed instructions that come with the kit for information about the correct way to mix and give a dose of raltegravir for oral suspension. If you have questions about how to mix or give raltegravir for oral suspension, talk to your health care provider or pharmacist.

Do not switch between the film-coated tablet, the chewable tablet, or the oral suspension without talking with your health care provider first.

Always take raltegravir in combination with other HIV medicines.

If you take too much raltegravir, 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 raltegravir, see the FDA drug label from DailyMed. (DailyMed is a federal website that includes the most recent drug labels submitted to FDA.)

What Should I Do if I Forget a Dose?

If you miss a dose of raltegravir, take the missed dose as soon as you remember it. But if it is almost time for your next dose, skip the missed dose and just take your next dose at the regular time. Do not take two doses at the same time to make up for a missed dose.

What Side Effects Can Raltegravir Cause?

Raltegravir can cause serious, life-threatening side effects. These include skin reactions, allergic reactions, and liver problems. (See the WARNING above.)

Other possible side effects of raltegravir include:

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 raltegravir. To learn more about possible side effects of raltegravir, 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 raltegravir.

You can also report side effects to FDA at 1-800-FDA-1088 (1-800-332-1088) or online at

How Should Raltegravir Be Stored?

Where Can I Find More Information About Raltegravir?

More information about raltegravir is available:

Manufacturer Information

Merck & Co., Inc.

The above Patient Version drug summary is based on the following FDA label(s): Tablet (chewable), tablet (film coated), granule for oral suspension.

This article was provided by AIDSinfo. You can find this article online by typing this address into your Web browser:

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