The length of a steroid taper depends on the disease and its severity. In the case of most autoimmune diseases such as Crohn's, it is better to taper off slowly for two reasons. 1) You need to suppress your body's immune reaction until it chills out. If you drop your steroid dose too quickly, the immune system can roar back with a vengeance, flaring worse than ever. 2) Steroids suppress your adrenal glands, which secrete glucocorticoids, mineralocorticoids, and androgens (stress hormones and hormones that regulate your electrolyte balance). If you stop the steroids, your body cannot rev up the adrenals fast enough to make up for the deficit. This can lead to shock, coma, and death.
Now that I have your attention...understand that steroid tapers can last from anywhere from a week to close to a year. The important thing to know is that if you are on chronic steroids or have recently been on steroids and find yourself hospitalized for something other than Crohn's (like a motorcycle accident or pneumonia), your doctors need to know that you are/were on steroids. Adrenal hormones kick into high gear under stress and illness. If you have been on low-dose steroids, your adrenal hormones will be suppressed and not working at full capacity.
Dr. S (spouse w/ crohn's)