- HIV AIDS Myths and Facts Slideshow Pictures
- Take the HIV/AIDS Quiz
- AIDS Retrospective Slideshow Pictures
- What is ritonavir, and how does it work (mechanism of action)?
- What brand names are available for ritonavir?
- Is ritonavir available as a generic drug?
- Do I need a prescription for ritonavir?
- What are the side effects of ritonavir?
- What is the dosage for ritonavir?
- Which drugs or supplements interact with ritonavir?
- Is ritonavir safe to take if I'm pregnant or breastfeeding?
- What else should I know about ritonavir?
What is ritonavir, and how does it work (mechanism of action)?
Ritonavir is an oral medication that is used for treating infections with the human immunodeficiency virus (HIV). It is in a class of drugs called protease inhibitors which also includes indinavir (Crixivan), nelfinavir (Viracept), emtricitabine (Emtriva) and saquinavir (Invirase, Fortovase). During infection with HIV, the HIV virus multiplies within the body's cells. Viruses are released from the cells and spread throughout the body where they infect other cells. In this manner, HIV infection is perpetuated among new cells that the body produces continually. During the production of the viruses, new proteins are made. Some of the proteins are structural proteins, that, is, proteins that form the body of the virus. Other proteins are enzymes which manufacture DNA and other components for the new viruses. Protease is the enzyme that forms the new structural proteins and enzymes. Ritonavir blocks the activity of protease and results in the formation of defective viruses that are unable to infect the body's cells. As a result, the number of viruses in the body (the viral load) decreases. Nevertheless, ritonavir does not prevent the transmission of HIV among individuals, and it does not cure HIV infections or AIDS. The FDA approved ritonavir in June 1999.
What are the side effects of ritonavir?
The most serious side effects are:
- liver failure,
- inflammation of the pancreas (pancreatitis),
- heart block, and
- severe allergic reactions.
Ritonavir also may elevate blood glucose resulting in new onset diabetes. Fat redistribution, elevated triglycerides, and elevated cholesterol levels also occur. Patients with hemophilia may experience spontaneous bleeding. Immune reconstitution syndrome which is an inflammatory response to infection may occur in patients treated with combination antiretroviral therapy.
Other important side effects include:
Quick GuideHIV AIDS Facts: Symptoms and Treatments
What is the dosage for ritonavir?
The recommended dose for adults is 600 mg twice daily. To reduce the occurrence of side effects, ritonavir should be started at 300 mg twice daily and increased every 2-3 days by 100 mg twice daily.
The recommended dose for children older than 1 month is 350 to 400 mg/m2 two times a day and should not exceed 600 mg two times daily. Treatment should be started at 250 mg/m2 and increased every 2-3 days by 50 mg/m2 two times daily.
Ritonavir should be administered with meals. The taste of the oral solution can be improved by mixing it with chocolate milk, Ensure or Advera for up to one hour before administration.
Which drugs or supplements interact with ritonavir?
Ritonavir interacts with many drugs. Some of the important interactions are mentioned below. Viewers should consult their healthcare provider before combining any drugs with ritonavir.
Ritonavir should not be used together with amiodarone (Cordarone), quinidine (Quinaglute, Cardioquin), triazolam (Halcion), midazolam (Versed), pimozide (Orap), ergot derivatives (for example, ergotamine, dihydroergotamine), alfuzosin (Uroxatral), propafenone (Rythmol) and flecainide (Tambocor) because ritonavir increases the blood levels of these drugs and may lead to serious side effects. Ritonavir should not be combined with voriconazole (Vfend) because it reduces blood levels of voriconazole.
Ritonavir also increases the concentrations in blood of rifabutin (Mycobutin) and sildenafil (Viagra). Therefore, the doses of rifabutin and sildenafil should be reduced. The blood concentrations of oral contraceptives, methadone (Dolophine) and theophylline (Theo-Dur, Theo-24) are reduced by ritonavir, and this could reduce the effectiveness of these drugs.
Ritonavir decreases the concentration of meperidine (Demerol) and increases the buildup of meperidine's toxic breakdown product in the body. Therefore, ritonavir reduces the beneficial effect of meperidine while increasing its side effects.
Ritonavir may increase the blood concentration of lovastatin (Mevacor), simvastatin (Zocor), and atorvastatin (Lipitor). This may result in increased occurrence of myopathy (muscle pain) or rhabdomyolysis (muscle breakdown). Lovastatin and simvastatin should not be combined with ritonavir.
St. John's wort and rifampin (Rifadin) decrease the concentration of ritonavir in the body and this could reduce the effectiveness of ritonavir.
Is ritonavir safe to take if I'm pregnant or breastfeeding?
Use of ritonavir during pregnancy has not been adequately evaluated. To monitor outcomes of pregnant women that received ritonavir, an Antiretroviral Pregnancy Registry has been established. Physicians are encouraged to register patients by calling 1-800-258-4263.
It is not known whether ritonavir is secreted in breast milk. Nevertheless, HIV-infected mothers should not breast-feed because of the potential risk of transmitting HIV to an infant that is not infected.
What else should I know about ritonavir?
What preparations of ritonavir are available?
Capsules or tablets: 100 mg; Solution: 80 mg/ml
How should I keep ritonavir stored?
Capsules that will not be used within 30 days should be stored in a refrigerator between 2 C to 8 C (36 F to 46F). Capsules that will be used within 30 days do not have to be refrigerated if stored at less than 25 C (77 F) Oral solution should be stored at room temperature, 20 C to 25 C (68 F to77 F).
Ritonavir (Norvir) is a drug used in combination with other drugs for the treatment of HIV infection. Side effects, drug interactions, and dosing information should be reviewed prior to taking this medication.
Multimedia: Slideshows, Images & Quizzes
Related Disease Conditions
Human Immunodeficiency Virus (HIV)
The human immunodeficiency virus (HIV) causes HIV infection and the acquired immunodeficiency syndrome (AIDS). Symptoms and signs...
Hepatitis C Cure (Symptoms, Transmission, Treatments, and Cost)
Hepatitis is inflammation of the liver. There are a variety of toxins, diseases, illicit drugs, medications, bacterial and viral...
Acquired Immunodeficiency Syndrome
AIDS is the advanced stage of HIV infection. Symptoms and signs of AIDS include pneumonia due to Pneumocystis jiroveci,...
Treatment & Diagnosis
- How To Reduce Your Medication Costs
- Pharmacy Visit, How To Get The Most Out of Your Visit
- Indications for Drugs: Approved vs. Non-approved
- Generic Drugs, Are They as Good as Brand-Names?
- Drugs: Buying Prescription Drugs Online Safely
- Medication Disposal - What to Do with Old or Unusable Medication
- Dangers of Mixing Medications
- Drugs: The Most Common Medication Errors
Medications & Supplements
- Drugs: What You Should Know About Your Drugs
- Drug Interactions
- Protease Inhibitors (PI Drug Class)
- atazanavir, Reyataz
- amprenavir, Agenerase
- lopinavir and ritonavir, Kaletra
- indinavir, Crixivan
- saquinavir, Invirase (Fortovase - discontinued)
- nelfinavir, Viracept
- darunavir, TMC-114; Prezista
- Technivie (ombitasvir, paritaprevir and ritonavir)
- tipranavir, Aptivus
- fosamprenavir - oral, Lexiva
Prevention & Wellness
- Illnesses, Deaths Spur FDA Warning on Hepatitis C Drugs
- Technivie Approved for Hepatitis C
- Antiviral Combination Approved for Hepatitis C
- Health Highlights: Dec. 22, 2014
- Cure Rate for Experimental Hepatitis C Drug Tops 95 Percent
- New Pills Show Promise for Hepatitis C
- Mom's HIV Drugs May Pass to Baby in Womb, Breast-Feeding
- Health Highlights: April 27, 2012
Daily Health News
Resources for Staying Well
Subscribe to MedicineNet's General Health Newsletter
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
Top ritonavir Related Articles
Acquired Immunodeficiency Syndrome (AIDS)AIDS is the advanced stage of HIV infection. Symptoms and signs of AIDS include pneumonia due to Pneumocystis jiroveci, tuberculosis, toxoplasmosis, seizures, weakness, meningitis, yeast infection of the esophagus, and Kaposi's sarcoma. Anti-retroviral therapy (HAART) is used in the treatment of AIDS.
amprenavirAmprenavir (Agenerase - discontinued brand) is a drug prescribed to treat infections with the human immunodeficiency virus (HIV). Side effects, drug interactions, and pregnancy safety information should be reviewed prior to taking this medication.
atazanavirAtazanavir (Reyataz) is a drug prescribed for the treatment of HIV infections. Side effects, drug interactions, and patient warnings should be reviewed prior to taking this medication.
darunavir, TMC-114Darunavir, TMC-114 (Prezista) is a protease inhibitor drug prescribed for the treatment of human immunodeficiency virus (HIV). Side effects, drug interactions, warnings and precautions, and patient information should be reviewed prior to taking any medication.
Drug InteractionsDrug interactions occur frequently. Get facts about the types of drug interactions, what substances or other things that may interact with drugs such as OTC drug and prescription drugs, vitamins, food(s) (grapefruit), and laboratory tests. Find out how to protect yourself from potential drug interactions.
Drugs: What You Should Know About Your DrugsImportant information about your drugs should be reviewed prior to taking any prescription drug. Side effects, drug interactions, warnings and precauctions, dosage, what the drug is used for, what to do if you miss a dose, how the drug is to be stored, and generic vs. brand names.
Hepatitis C Cure Symptoms and Treatment Costs
Hepatitis is inflammation of the liver. There are a variety of toxins, diseases, illicit drugs, medications, bacterial and viral infections, and heavy alcohol use can case inflammation of the liver. Hepatitis C viral infection (HCV) is one type of hepatitis. According to the CDC, in 2014 there were an estimated 30,500 cases of acute hepatitis C infections in the US. An estimated 2.7-3.9 million people in the US have chronic hepatitis C. The virus is spread from person-to-person via blood-to-blood contact.
Symptoms of HCV infection include joint pain, jaundice, dark urine, nausea, fatigue, fever, loss of appetites, clay colored stool. Hepatitis C can be cured with medications in most people. There is no vaccine against the hepatitis C virus.
HIV TestingHIV antibody tests detect antibodies the body produces to neutralize the virus. HIV RNA testing uses polymerase chain reaction to detect HIV RNA in a person's blood. It usually takes one to three days to get results.
HIV/AIDS PictureAcronym for the Human Immunodeficiency Virus, the cause of AIDS (acquired immunodeficiency syndrome). See a picture of HIV/AIDS and learn more about the health topic.
Human Immunodeficiency Virus (HIV)The human immunodeficiency virus (HIV) causes HIV infection and the acquired immunodeficiency syndrome (AIDS). Symptoms and signs of HIV infection include fatigue, enlarged lymph glands, and recurrent vaginal yeast infections. Highly active antiretroviral therapy (ART) is the standard treatment for HIV infection.
indinavirIndinavir (Crixivan) is a medication prescribed for the treatment of infections with the human immunodeficiency virus (HIV). Side effects, dosing, and in particular, drug interactions should be discussed with our health care professional prior to taking this medication.
lopinavir and ritonavirLopinavir and ritonavir (Kaletra) is a drug that is a combination of lopinavir and ritonavir that is prescribed to treat human immunodeficiency virus (HIV). Side effects , drug interactions, pregnancy information, and warnings and precautions should be reviewed prior to taking this medication.
nelfinavirNelfinavir (Viracept) is a drug prescribed to be used in combination with other anti-HIV drugs to treat HIV infection. Side effects, drug interactions, dosage, and pregnancy safety should be reviewed prior to taking this medication.
Protease Inhibitors (PI) Drug Class
Protease Inhibitors (PIs) are a class of antiviral drugs prescribed to treat HIV and hepatitis (HCV) viral infections. There are several protease inhibitors that treat HIV infection, for example:
- Lexiva (fosamprenavir)
- Invirase (saquinavir)
- Kaletra (lopinavir/ritonavir)
- Viracept (nelfinavir)
- Norvir (ritonavir)
Examples of hepatitis C virus protease inhibitors include:
- Olysio (simeprevir)
- Technivie (ombitasvir/paritaprevir and ritonavir, a combination of these three drugs)
- Viekira Pak (ombitasvir/paritaprevir/ritonavir and dasabuvir, a combination of these four drugs)
Drug interactions, dosage, preparations, and pregnancy and breastfeeding safety should be reviewed prior to taking these drugs.
TechnivieTechnivie (ombitasvir, paritaprevir and ritonavir) is a combination drug prescribed to treat heptatitis C in patients without liver cirrhosis. Side effects, drug interactions, dosing, storage, and pregnancy and breastfeeding information should be reviewed prior to taking this medication