Dexamethasone is a strong corticosteroid (steroid), very similar to the hormones produced by adrenal glands. When levels of this hormone are low in the body, Dexamethasone is used to treat a wide variety of conditions including skin diseases and edema (fluid retention), along with certain types of arthritis, severe allergies and internal disorders. Dexamethasone injections are used to treat inflammation of the brain, kidneys, thyroid and eyes as well as some types of cancer.
Generally, Dexamethasone reaches peak effectiveness within 10-30 minutes of being administered but can take up to a few days to sufficiently reduce inflammation.