Everolimus is an immunosuppressant medication primarily used to prevent organ rejection in transplant patients and to treat certain types of cancers. It works by inhibiting the mTOR pathway, which plays a key role in cell growth, proliferation, and survival. Everolimus is often prescribed for renal cell carcinoma, pancreatic neuroendocrine tumors, and in certain heart, kidney, and liver transplants. Common side effects include mouth sores, increased risk of infection, and fatigue, so regular monitoring is essential to manage potential adverse effects.