Corticosteroids are a class of chemicals that include steroid hormones produced naturally in the adrenal cortex. They affect stress response, immune response, and inflammation. Corticosteroids work in the body by entering cells and inhibiting the enzyme that produces arachidonic acid, which leads to reduced inflammation. Common corticosteroids include dexamethasone, cortisone, hydrocortisone, methylprednisone, prednisolone, and prednisone. While they can treat conditions like asthma and arthritis, prolonged high doses can cause side effects like Cushing's syndrome, osteoporosis, and hypokalemia.