How long does it take for corticosteroids to work on eczema?

Depends.: It depends on the strength of the steroid. Usually you may start showing some improvement in 24-36 hours. Avoid fragrances in lotions, soaps, detergents, hot water,and scratching! Also pat, don't rub dry and be sure to use a good moisturizer for sensitive skin. If you have no change at all in 3 days, call your doc and find out what to try next.

Eczema: Topical corticosteroids should take a couple of days to see improvement of your skin, but relief from the itching should improve within a couple of hours. You should work to keep your skin well hydrated with hypoallergenic lotion through out the day, likely applying lotion more than three times. This will allow you to limit using the steroids. If extensive eczema, see a Dermatologist for more care