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Uses

What is ritonavir used for?

Ritonavir is commonly used for the treatment of HIV (in combination with other medicine).

Ritonavir may also be used for other conditions as determined by your healthcare provider.

How does ritonavir work (mechanism of action)?

People with HIV have a virus that spreads in their body and damages the immune system, making it easier for them to get very sick from other infections. Ritonavir works together with other medicines to help stop the spread of HIV in your body. This helps protect and preserve the immune system and can prevent the virus from being spread to other people.

How is ritonavir supplied (dosage forms)?

Brands and other names

  • Norvir

Dosage forms and strengths

  • 100 mg oral tablets
  • 100 mg/packet oral powder

How should I store ritonavir?

Tablets. Ritonavir tablets should be stored in the original container at or below 86 F (30 C). It can be exposed to temperatures up to 122 F (50 C) for shorter periods of time, such as when transporting it. Store tightly closed in a cool, dry place. Protect from moisture.

Powder Packet. Ritonavir powder packets should be stored at or below 86 F (30 C). Store in a cool, dry place. Do not open the foil packets until you are ready to take the medicine.

Side Effects

What are the most common side effects of ritonavir?

The most common side effects of ritonavir are listed below. Tell your healthcare provider if you have any of these side effects that bother you.

  • Nausea, vomiting, or diarrhea
  • Stomach pain
  • Numbness, tingling, or burning in your arms, feet, face, or mouth
  • Feeling unusually weak or tired
  • Rash

There may be other side effects of ritonavir that are not listed here. Contact your healthcare provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088. In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of ritonavir?

While less common, the most serious side effects of ritonavir are described below, along with what to do if they happen.

Liver Damage. Liver damage, also called hepatotoxicity, can happen when taking ritonavir. Call your healthcare provider right away if you have any of the following symptoms of liver damage.

  • Nausea or vomiting
  • Stomach or belly pain
  • Fever
  • Weakness or unusual tiredness
  • Itching
  • Loss of appetite
  • Light-colored poop
  • Dark-colored urine (pee)
  • Your skin or the whites of your eyes turning yellowish in color (also called jaundice)

Inflammation of the Pancreas (Pancreatitis). Ritonavir may cause inflammation of the pancreas, which is called pancreatitis. Stop taking ritonavir and call your healthcare provider right away if you have symptoms of pancreatitis, including vomiting or severe pain in the upper part of your belly that travels to your back.

Heart Rhythm Changes. Ritonavir may cause heart rhythm problems that can lead to an irregular heartbeat and fainting. In rare cases, this may cause the heart to suddenly stop beating (cardiac arrest). Some people have a higher risk of this, including people with existing heart disease or who take other medicines that affect the heart. Get emergency help if you have any of the following signs of heart rhythm changes.

  • Chest pain
  • Shortness of breath
  • Feeling dizzy, lightheaded, or fainting
  • Changes in your heart rate or rhythm, such as a fast, slow, pounding or skipping heartbeat

Metabolism Problems. Ritonavir can cause high blood sugar levels or diabetes, and high cholesterol levels. Keep all appointments with your healthcare provider to check your blood work. Call your healthcare provider if you gain weight or develop the following symptoms of high blood sugar.

  • Thirsty more than usual
  • Peeing more than usual
  • Increase in hunger
  • Tiredness
  • Feeling sick to your stomach
  • Confusion
  • Your breath smelling fruity

Immune System Changes. When you start ritonavir, your immune system might get stronger and start fighting infections that have been hiding inside your body for a long time. The type of symptoms you may have will depend on the infection. Tell your healthcare provider right away if you notice any of the following new symptoms of infection.

  • Fever, sweats, chills, or muscle aches
  • Swollen lymph nodes
  • Vision problems
  • Confusion, problems talking, or headache
  • Skin problems such as a painful rash or warts
  • Cough or coughing up blood
  • Weakness or coordination problems

Change in Body Fat. Some people taking ritonavir have noticed changes in how their body stores fat. This can include gaining fat around the stomach, back of the neck, or chest, while losing fat in other areas like the arms, legs, or face. Tell your healthcare provider right away if you notice any of these changes. 

Severe Skin Reactions. Ritonavir can cause severe skin reactions, called Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN), that can lead to death if not treated. If you develop a rash, stop ritonavir and call your healthcare provider right away. Get emergency help if you have any of the following symptoms of SJS or TEN.

  • Painful red or purple skin that looks burned and peels off
  • Flat red rash or blisters on your skin, mouth, nose, and genitals
  • Red, painful, watery eyes

Severe Allergic Reactions. Ritonavir may cause allergic reactions, which can be serious. Stop taking ritonavir and get help right away if you have any of the following symptoms of a serious allergic reaction.

  • Breathing problems or wheezing
  • Racing heart
  • Fever or general ill feeling
  • Swollen lymph nodes
  • Swelling of the face, lips, mouth, tongue, or throat
  • Trouble swallowing or throat tightness
  • Itching, skin rash, or pale red bumps on the skin called hives
  • Nausea or vomiting
  • Dizziness, feeling lightheaded, or fainting
  • Stomach cramps
  • Joint pain

Warnings & Precautions

Who should not use ritonavir?

Allergies to Ingredients. People who are allergic to any of the following should not take ritonavir.

  • Norvir
  • Ritonavir
  • Any of the ingredients in the specific product dispensed

Your pharmacist can tell you all of the ingredients in the specific ritonavir products they stock.

Drug Interactions. Ritonavir should not be taken while you are using certain other medicines. Before taking ritonavir, tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. See the Interactions section for more details.

What should I know about ritonavir before using it?

Do not take ritonavir unless it has been prescribed to you by a healthcare provider. Take it as prescribed.

Take each dose of ritonavir with food. You can mix the powder with soft food like applesauce or vanilla pudding or liquid such as chocolate milk or infant formula.

If you are taking the tablet form of ritonavir, make sure to swallow it whole. Do not chew or crush it.

Do not share ritonavir with other people, even if they have the same condition as you. It may harm them.

Keep ritonavir out of the reach of children.

While ritonavir (in combination with other medicine) can help keep the HIV infection under control, it does not cure it. Also, ritonavir does not help protect against or prevent the spread of sexually transmitted infections (STIs), like herpes, gonorrhea, or chlamydia.

What should I tell my healthcare provider before using ritonavir?

Tell your healthcare provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them determine if ritonavir is right for you.

In particular, make sure that you discuss any of the following.

Current and Past Health Conditions. Tell your healthcare provider if you have any of the following.

  • Heart disease
  • Liver problems, including hepatitis B or C
  • Diabetes
  • Blood disorder, such as hemophilia
  • Pancreas problems

Birth Control Medicine. Ritonavir can make certain types of birth control medicine less effective. If you take or use birth control medicine, talk to your healthcare provider about how ritonavir may affect it and the potential need for alternative or additional birth control methods. 

Pregnancy. It is not known if or how ritonavir could affect pregnancy or harm an unborn baby. Tell your healthcare provider if you are or plan to become pregnant. Your healthcare provider will advise you if you should take ritonavir while you are pregnant or trying to get pregnant. If you become pregnant while taking ritonavir, you can register for the Antiretroviral Pregnancy Registry by visiting www.apregistry.com. This registry collects safety information about the use of HIV medicines during pregnancy.

Breastfeeding. Do not take ritonavir while you are breastfeeding. Ritonavir passes into breast milk. Tell your healthcare provider if you are breastfeeding or plan to breastfeed. There may be risks with breastfeeding while taking ritonavir and having HIV.

Interactions

Does ritonavir interact with foods or drinks?

There are no known interactions between ritonavir and foods or drinks.

 It is unknown if drinking alcohol will affect ritonavir.

Does ritonavir interact with other medicines (drug interactions)?

Always tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. 

In particular, make sure you discuss if you are using any of the following before taking ritonavir.

  • Alfuzosin, which is a medicine that may be used for difficulty peeing due to an enlarged prostate
  • Ranolazine (Aspruzyo Sprinkle), which is a medicine used for chest pain
  • A medicine used to control your heart rate or rhythm (antiarrhythmic)
  • A medicine used for treating a fungal infection
  • Colchicine, which is commonly used for gout
  • An antipsychotic, which is a medicine for certain mental health conditions
  • An ergot, such as ergotamine (Ergomar) or dihydroergotamine (Migranal or Trudhesa), which is a medicine used to treat migraine
  • A medicine to lower cholesterol, such as lovastatin, simvastatin, or lomitapide (Juxtapid)
  • A phosphodiesterase-5 (PDE-5) inhibitor, such as sildenafil (Viagra, Revatio, and others), which is a medicine used for erectile dysfunction and pulmonary arterial hypertension (PAH)
  • Triazolam or midazolam, which is a medicine used for anxiety, muscle spasms, or seizures
  • St. John’s wort, which is a supplement that may be used to treat depression 
  • A medicine for cancer 
  • Any other medicine for HIV or AIDS
  • Any medicine for hepatitis B or C
  • A medicine for birth control
  • A blood thinner, which is a medicine used to treat or prevent blood clots
  • A corticosteroid, such as dexamethasone, methylprednisolone, or prednisone, which is a medicine for certain inflammatory conditions, asthma, or COPD

Many other medicines may alter the blood levels of ritonavir, and vice versa. Tell your healthcare provider about all medicines that you take or have recently taken.

This may not be a complete list of medicines that can interact with ritonavir. Always check with your healthcare provider.

Does interact with other drugs you are taking?

Enter your medication into the WebMD interaction checker

Overdose/Missed Dose

What should I do if I accidentally use too much ritonavir?

If you or someone else has used too much ritonavir, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

What should I do if I miss a dose of ritonavir?

If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and only take the next dose. Do not take double or extra doses.

Missing doses of ritonavir can cause it to not work as well over time. So it is very important not to miss or skip doses.