Preventing Cushing: Iatrogenic Cushing Syndrome due to Ritonavir-Fluticasone Interaction.

Ritonavir is commonly used in low doses to boost plasma levels of protease inhibitors in patients with human immunodeficiency virus (HIV) infections. It is also a potent inhibitor of cytochrome P450. We present a 50-year-old African American male with past medical history of HIV on highly active antiretroviral therapy (HAART), which also included ritonavir and long standing asthma that has been treated with inhaled fluticasone, who presented with back pain.