Tenofovir is an antiviral medicine that works by blocking the virus from multiplying in the body. It is widely used in three main ways: ✅ HIV treatment - always combined with other medicines as part of antiretroviral therapy (ART). ✅ HIV prevention (PrEP) - taken by HIV-negative people at high risk to reduce their chances of getting HIV. ✅ Chronic Hepatitis B - helps lower the amount of virus in the body, protecting the liver from long-term damage. Tenofovir is available in different forms, incl