Indinavir sulfate is primarily used in the treatment of HIV infection. It works by inhibiting the protease enzyme, which is essential for the replication of the virus. This helps to reduce the viral load in the body and slows the progression of the disease. It is often prescribed as part of a combination therapy with other antiretroviral drugs to enhance its effectiveness and reduce the risk of developing drug resistance. Patients taking this medication must adhere strictly to their prescribed regimen to maintain its therapeutic benefits. Additionally, it is important to monitor for potential side effects, which can include kidney stones, gastrointestinal issues, and changes in fat distribution. Proper hydration is recommended to minimize the risk of kidney-related complications.