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Norvir (ritonavir)

Type of Drug: Protease Inhibitor
Once HIV has infected a cell and made copies of itself, it uses an enzyme called protease to process itself correctly so it can be released from the cell to infect other cells. Protease inhibitors work by blocking that enzyme.

Norvir was originally taken as 600 mg twice a day, but few patients can tolerate this and it is rarely prescribed in this way anymore. Instead, "low-dose" Norvir (usually 100 mg) is often used with each dose of certain other HIV medications to boost their levels.

100 mg tablet

  • Norvir 100 tablet


100 mg capsule

  • Norvir 100 capsule


Notes on taking this medication

  • Used as a booster of other protease inhibitors; must be taken with one of these
  • Should take with food
  • Norvir interacts with many other drugs; persons using Norvir with those drugs may need an adjustment to their dose of Norvir or the other drugs; consult your medical provider

Side effects

  • Many side effects including nausea; vomiting; diarrhea; loss of appetite; stomach discomfort
  • Tingling and numbness around the mouth
  • Liver inflammation and increased liver enzyme levels
  • Elevations in cholesterol and triglycerides
  • Elevated blood sugar
  • Abnormal accumulation of body fat

See accompanying chart: Tips for Common Side Effects

My doctor's instructions

Scroll over drug name to see other names for the drug.