Ritonavir

pronounced as (ri toe' na veer)

Brand Name(s): Norvir®

Why is this medicine prescribed?

Ritonavir is used to treat human immunodeficiency virus (HIV) infection. Ritonavir is in a class of medications called protease inhibitors. It works by decreasing the amount of HIV in the blood.

Although ritonavir does not cure HIV, it may decrease your chance of developing acquired immunodeficiency syndrome (AIDS) and HIV-related illnesses. Taking these medications and making other lifestyle changes may decrease the risk of transmitting the HIV virus to other people.

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?

Ritonavir comes as a tablet and a powder to mix with soft foods or liquid to take by mouth. Take twice a day with meals.

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

Your doctor will probably start you on a low dose of ritonavir and gradually increase your dose, not more often than once every 2 to 3 days. Follow these directions carefully.

Swallow ritonavir tablets whole. Do not split, chew, or crush them.

To prepare the powder, mix the contents of the packet(s) for your dose and pour over soft food, such as applesauce or vanilla pudding, in a small bowl or cup. The powder also may be mixed with liquid in a drinking glass. Mix well and use within 2 hours after preparation. If there is powder left in bowl, cup, or drinking glass, add more soft food or liquid to the container and take the rest of that mixture right away. If not used within 2 hours, discard the mixture. For use in a feeding tube, mix the powder with water and give according to directions.

Continue to take ritonavir even if you feel well. Do not stop taking ritonavir without talking to your doctor. If you miss doses, take less than the prescribed dose, or stop taking ritonavir, your condition may become more difficult to treat.

What special precautions should I follow?

Before taking ritonavir,

  • tell your doctor or pharmacist if you are allergic to this drug, any part of this drug, or any other drugs, foods or substances. Tell your doctor or pharmacist about the allergy and what symptoms you had.
  • some medications should not be taken with ritonavir. Other medications may cause dosing changes or extra monitoring when taken with ritonavir. Make sure you have discussed any medications you are currently taking or plan to take before starting ritonavir with your doctor and pharmacist. Before starting, stopping, or changing any medications while taking ritonavir, please get the advice of your doctor or pharmacist.
  • the following herbal product may interact with ritonavir: St. John's wort. Be sure to let your doctor and pharmacist know that you are taking this medication before you start taking ritonavir. Do not start this medication while taking ritonavir without discussing with your healthcare provider.
  • you should know that ritonavir may decrease the effectiveness of hormonal contraceptives (birth control pills, patches, rings, or injections). You will need to use another method of contraception to prevent pregnancy while taking ritonavir. 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 diabetes, hemophilia, high cholesterol or triglycerides (fats) in the blood, or heart or liver disease, including hepatitis B or C.
  • tell your doctor if you are pregnant, or plan to become pregnant. If you become pregnant while taking ritonavir, call your doctor immediately.
  • 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 ritonavir.
  • you should be aware that your body fat may increase or move to different areas of your body, such as your upper back, neck (''buffalo hump''), breasts, and around your stomach. You may notice a loss of body fat from your face, legs, and arms.
  • you should know that you may experience hyperglycemia (increases in your blood sugar) while you are taking this medication, even if you do not already have diabetes. Tell your doctor immediately if you have any of the following symptoms while you are taking ritonavir: extreme thirst, frequent urination, extreme hunger, blurred vision, or weakness. It is very important to call your doctor as soon as you have any of these symptoms, because high blood sugar that is not treated can cause a serious condition called ketoacidosis. Ketoacidosis may become life-threatening if it is not treated at an early stage. Symptoms of ketoacidosis include dry mouth, nausea and vomiting, shortness of breath, breath that smells fruity, and decreased consciousness.
  • you should know that while you are taking medications to treat HIV infection, your immune system may get stronger and begin to fight other infections that were already in your body. This may cause you to develop symptoms of those infections. If you have new or worsening symptoms after starting treatment with ritonavir, be sure to tell your doctor.

What special dietary instructions should I follow?

Unless your doctor tells 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.

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.

Symptoms of overdose may include the following:

  • numbness, burning, or tingling of the hands or feet

What side effects can this medicine cause?

Ritonavir may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • diarrhea
  • numbness, burning, or tingling of the hands, feet, or area around the mouth
  • tiredness, weakness

Some side effects can be serious. If you experience any of the following symptoms, call your doctor immediately or get emergency medical treatment:

  • rash; hives; blistering or peeling of the skin; swelling of the eyes, face, tongue, lips, or throat; difficulty breathing or swallowing
  • nausea, vomiting, abdominal pain that may go around to your back
  • stomach pain, loss of appetite; pain in the upper right part of the stomach; yellowing of the skin or eyes;
  • dizziness, lightheadedness, loss of consciousness, irregular heartbeat

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).

Ritonavir may cause other side effects. Call your doctor if you have any unusual problems while you are taking this medication.

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 the tablets and powder at room temperature. You may store the tablets at higher temperatures for up to 7 days and expose high humidity for up to 2 weeks..

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 other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your response to ritonavir.

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.

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