Ritonavir
Ritonavir is an antiretroviral protease inhibitor often used at a boosting level to slow the breakdown of another medicine. Its strong effect on drug metabolism creates many clinically important interactions.
Key points
- Ritonavir is usually one component of a complete antiviral regimen and should not be started or stopped independently.
- Prescription medicines, over-the-counter products, recreational substances and herbal supplements can interact seriously with ritonavir.
- A combination product containing ritonavir is not interchangeable with ritonavir alone or with a different boosted regimen.
Listings are for comparison only; suitability and supply depend on specialist regimen review, interaction screening, prescription and pharmacy checks.
What ritonavir is used for
Ritonavir is used within selected treatment for HIV infection and as a pharmacokinetic booster in some other antiviral regimens. The companion medicines determine the regimen’s purpose.
How it works
Ritonavir inhibits HIV protease and strongly inhibits enzymes that metabolise many medicines. At boosting levels, this raises and prolongs exposure to a companion antiviral.
Important safety checks
Every medicine and supplement should be screened for interactions before it is started, stopped or changed. The specialist may also review liver disease, heart rhythm, diabetes, bleeding risk and the complete antiretroviral history. Never assume that a familiar medicine is compatible.
When to seek urgent care
Seek urgent help for fainting, a new irregular heartbeat, severe weakness, yellow skin or eyes, severe abdominal pain, blistering skin, facial swelling or breathing difficulty. Contact the treatment team promptly after a missed regimen or accidental interacting medicine rather than adjusting treatment alone.