Hydrocortisone is a drug used to suppress __________.

Hydrocortisone is a corticosteroid medication that is primarily used for its anti-inflammatory properties. It works by mimicking the effects of hormones that are naturally produced in the adrenal glands, which help regulate inflammation and immune responses in the body. When hydrocortisone is administered, it leads to reduced swelling, redness, and pain associated with inflammatory conditions. This makes it particularly effective in treating various inflammatory disorders, such as arthritis, skin rashes, and certain allergies.

The other choices, while they may relate to some of the uses of corticosteroids, do not capture the primary function of hydrocortisone as specifically as inflammation does. For instance, while hydrocortisone can help with allergic reactions, its main mechanism is to suppress inflammation, which is a key attribute for many conditions being treated. Therefore, the focus on inflammation as the correct answer highlights the drug's primary therapeutic effect.