Norvir (Ritonavir) is an antiretroviral medication primarily used to treat HIV (Human Immunodeficiency Virus). It is classified as a protease inhibitor. Ritonavir is often used in combination with other HIV medications to enhance their effectiveness, as it boosts the concentration of other protease inhibitors in the body.
Product Highlights
Ritonavir is used to treat HIV infection in adults and children as part of a combination antiretroviral regimen.
In some cases, Ritonavir may be part of a post-exposure prophylaxis (PEP) regimen.
Ritonavir is often used in smaller doses as a booster for other protease inhibitors (such as lopinavir) due to its ability to inhibit the enzyme that metabolizes these drugs, thereby increasing their effectiveness.
Key Ingredient
Ritonavir
Key Benefits
Ritonavir helps lower the viral load in patients with HIV, thereby improving immune function and reducing the risk of developing AIDS.
When used in combination, ritonavir enhances the effectiveness of other protease inhibitors, making them more potent.
Ritonavir can reduce the number of pills a patient needs to take by boosting other medications, which may improve adherence to antiretroviral therapy.
Directions for Use
The recommended dose of ritonavir depends on whether it is being used as a monotherapy or as a booster for other antiretrovirals. Typically, ritonavir is taken with food to increase absorption.
Oral Tablet: Usually taken once or twice daily.
Oral Solution: Shake well before use and measure the dose carefully using a dosing syringe or cup.
The capsule form may be taken whole or opened and mixed with food or liquid if needed. It can be taken with or without food.
Pediatric Dosage Guidelines for Oral Solution*
Body Surface Area (m2 )
Twice Daily Dose 250 mg per m2
Twice Daily Dose 300 mg per m2
Twice Daily Dose 350 mg per m2
Twice Daily Dose 400 mg per m2
0.20
0.6 mL (50 mg)
0.75 mL (60 mg)
0.9 mL (70 mg)
1.0 mL (80 mg)
0.25
0.8 mL (62.5 mg)
0.9 mL (75 mg)
1.1 mL (87.5 mg)
1.25 mL (100 mg)
0.50
1.6 mL (125 mg)
1.9 mL (150 mg)
2.2 mL (175 mg)
2.5 mL (200 mg)
0.75
2.3 mL (187.5 mg)
2.8 mL (225 mg)
3.3 mL (262.5 mg)
3.75 mL (300 mg)
1.00
3.1 mL (250 mg)
3.75 mL (300 mg)
4.4 mL (350 mg)
5 mL (400 mg)
1.25
3.9 mL (312.5 mg)
4.7 mL (375 mg)
5.5 mL (437.5 mg)
6.25 mL (500 mg)
Safety Concerns
Ritonavir has a high potential for drug interactions. It affects liver enzymes (CYP450), especially CYP3A4, and can increase or decrease the blood levels of many other drugs. Patients should disclose all other medications they are taking to their healthcare provider.
Ritonavir can cause liver toxicity, especially in individuals with pre-existing liver disease, and should be used with caution in these patients.
Common side effects include nausea, vomiting, diarrhea, and abdominal pain.
Ritonavir can cause QT interval prolongation and should be used with caution in patients with arrhythmias.
Long-term use can lead to body fat redistribution (lipodystrophy), including fat accumulation in the abdominal area.
Avoid Norvir (Ritonavir) If
You are allergic to ritonavir or any of the ingredients in Norvir.
You have severe liver disease, including cirrhosis.
You are taking certain medications that interact with ritonavir and cannot be safely combined. These include some antiarrhythmics, certain statins, sedatives, or medications used for seizures or fungal infections.
You are pregnant (unless recommended by a doctor for a specific treatment regimen).
You have a history of severe allergic reactions to other protease inhibitors.
You have certain heart conditions, such as a prolonged QT interval or arrhythmias.
