Drug Database: Ritonavir

What is ritonavir?

Ritonavir (brand name: Norvir) is a prescription medicine approved by the U.S. Food and Drug Administration (FDA) for the treatment of HIV infection in adults and children older than 1 month. Ritonavir is always used in combination with other HIV medicines.

Although ritonavir is FDA-approved for the treatment of HIV infection, it is no longer used for its activity against HIV. Instead, ritonavir (given at low doses) is currently used as a pharmacokinetic enhancer to boost the activity of other HIV medicines.

When ritonavir is used as a pharmacokinetic enhancer, it does not work as an HIV medicine and does not treat HIV. You must take all the HIV medicines prescribed by your health care provider. Do not cut down on, skip, or stop taking ritonavir or any HIV medicines unless your health care provider tells you to.

For more information on the use of ritonavir in people with HIV, please refer to the Guidelines for the Use of Antiretroviral Agents in Adults and Adolescents Living with HIV and the Guidelines for the Use of Antiretroviral Agents in Pediatric HIV Infection.

What should I tell my health care provider before taking ritonavir?

Before taking ritonavir, tell your health care provider:

• If you are allergic to ritonavir or any other medicines.
• If you have liver problems, including hepatitis B virus infection (HBV) or hepatitis C virus infection (HCV).
• If you have heart problems.
• If you have diabetes or high blood sugar (hyperglycemia).
• If you have bleeding problems or hemophilia.
• If you have any other medical conditions.
• If you are pregnant or plan to become pregnant. You should not take ritonavir oral solution while pregnant. Ritonavir oral solution contains alcohol, and there is no known safe level of alcohol exposure during pregnancy. Talk to your health care provider about the risks and benefits of taking ritonavir during pregnancy. For more information on the use of ritonavir during pregnancy, please refer to the Recommendations for the Use of Antiretroviral Drugs in Pregnant Women with HIV Infection and Interventions to Reduce Perinatal HIV Transmission in the United States.
• If you are breastfeeding or plan to breastfeed. For women with HIV in the United States, the Guideline does not recommend breastfeeding. Before your baby is born, or if you are already breastfeeding, talk to your health care provider to discuss alternative options for feeding your baby.
• If you are using hormone-based birth control (such as pills, implants, or vaginal rings). Ritonavir may make these forms of birth control less effective. Your health care provider can help you decide how to adjust your birth control while you are taking ritonavir. For more information about using birth control and HIV medicines at the same time, view the HIVinfo HIV and Birth Control infographic.
• About other prescription and nonprescription medicines, vitamins, nutritional supplements, and herbal products (particularly St. John's wort) you are taking or plan to take. Ritonavir may affect the way other medicines or products work, and other medicines or products may affect how ritonavir works. Taking ritonavir together with certain medicines or products may cause serious, life-threatening side effects.

How should I take ritonavir?

Ritonavir comes in the following forms and strengths:

• 100-mg tablets
• 80-mg/mL oral solution
• 100-mg/packet oral powder

Take ritonavir according to your health care provider’s instructions.

Take ritonavir with meals.

Swallow ritonavir tablets whole. Do not chew, break, or crush the tablets before swallowing.

Ritonavir oral solution is a peppermint- or caramel-flavored liquid that can be taken alone or mixed with 8 ounces of chocolate milk, Ensure®, or Advera® to improve the taste. (When mixed with these fluids, ritonavir oral solution should be taken within 1 hour of mixing.) Shake well before each use.

Ritonavir oral solution contains a large amount of alcohol. Because of this, a toddler or young child can become sick from accidentally drinking more than the recommended dose of ritonavir. If this happens, go to the nearest hospital emergency room immediately.

Ritonavir oral powder comes in individual packets and is an option for children. The oral powder is mixed into a spoonful or more of soft food (such as applesauce or pudding) or liquid (such as water, chocolate milk, or infant formula). The bitter aftertaste of ritonavir oral powder may be lessened if it’s taken with food. All of the mixture should be taken. The mixture must be given within 2 hours of mixing with the food or liquid. If it’s not given within 2 hours of mixing, throw away the mixture and prepare a new dose. See the “Instructions for Use” that come with ritonavir oral powder for complete information about how to prepare and give or take a dose of ritonavir.

Always take ritonavir in combination with other HIV medicines.

If you have taken too much ritonavir, 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 ritonavir, see the FDA drug label.

What should I do if I forget a dose?

If you miss a dose of ritonavir, 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 ritonavir cause?

Ritonavir may cause side effects. Some side effects of ritonavir can be serious as noted above. Many side effects from HIV medicines, such as nausea or occasional dizziness, are manageable. See the HIVinfo fact sheet on HIV Medicines and Side Effects for more information.

Other possible side effects of ritonavir include:

• Increases in levels of cholesterol and triglycerides.
• Diabetes and high blood sugar (hyperglycemia).
• Changes in your immune system (called immune reconstitution inflammatory syndrome or IRIS). IRIS is a condition that sometimes occurs when the immune system begins to recover after treatment with an HIV medicine. As the immune system gets stronger, it may have an increased response to a previously hidden infection.
• Changes in body fat (lipodystrophy syndrome).
• Increased bleeding in people with hemophilia.
• Kidney stones.

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 ritonavir. To learn more about possible side effects of ritonavir, read the drug label or package insert or talk to your health care provider or pharmacist.

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

How should ritonavir be stored?

Keep ritonavir in the container that it came in and keep the container tightly closed. Do not use ritonavir if the original seal over the container opening is broken or missing.

Follow specific storage instructions for ritonavir tablets, oral solution, and oral powder.

Ritonavir tablets:

• Store ritonavir tablets below 86°F (30°C). Ritonavir tablets can be exposed to temperatures up to 122°F (50°C) for up to 7 days.
• If ritonavir tablets are not stored in their original container, don’t expose the tablets to high humidity for longer than 2 weeks.

Ritonavir oral solution:

• Store ritonavir oral solution at room temperature, 68°F to 77°F (20°C to 25°C).
• Don't refrigerate ritonavir oral solution and keep it away from heat.

Ritonavir oral powder:

• Store ritonavir oral powder at or below 86°F (30°C).

Throw away ritonavir that is no longer needed or expired (out of date). Follow FDA guidelines on how to safely dispose of unused medicine. Keep ritonavir and all medicines out of reach of children.

Where can I find more information about ritonavir?

• For more information on the use of ritonavir in people with HIV, please refer to the Guidelines for the Use of Antiretroviral Agents in Adults and Adolescents Living with HIV and the Guidelines for the Use of Antiretroviral Agents in Pediatric HIV Infection.
• The above Patient Version drug summary is based on the following FDA label(s): Tablet (film coated), solution, powder. The Patient Counseling Information section of the label includes information for people taking ritonavir.
• Ritonavir-related research studies, from ClinicalTrials.gov.
• A list of FDA-approved HIV medicines, from HIVinfo.