If too much corticosteroid cream becomes absorbed through the skin, serious complications can result, including adrenal gland suppression and Cushing's syndrome. In adrenal gland suppression, the body stops manufacturing its own steroids, so the patient may become dependent on the drug. Cushing's syndrome causes symptoms including diabetes, high blood pressure , and muscle weakness. Local side effects are also possible due to misuse of corticosteroid cream. These can include skin atrophy, stretch marks , susceptibility to infection, allergy , easily bruised or injured skin, and enlarged blood vessels.
There is no evidence of safe and effective use of topical corticosteroids in pregnant mothers. Therefore, they should be used only if clearly needed. Long term use and large applications of topical corticosteroids may cause birth defects in the unborn. It is not known whether topical corticosteroids enter breast milk. Therefore, caution must be exercised before using it in nursing mothers. Topical corticosteroids should not be applied to the breasts of nursing mothers unless the mothers instructed to do so by the physician.
Lewis Sarett of Merck & Co. was the first to synthesize cortisone, using a 36-step process that started with deoxycholic acid, which was extracted from ox bile .  The low efficiency of converting deoxycholic acid into cortisone led to a cost of US $200 per gram. Russell Marker , at Syntex , discovered a much cheaper and more convenient starting material, diosgenin from wild Mexican yams . His conversion of diosgenin into progesterone by a four-step process now known as Marker degradation was an important step in mass production of all steroidal hormones, including cortisone and chemicals used in hormonal contraception .  In 1952, . Peterson and . Murray of Upjohn developed a process that used Rhizopus mold to oxidize progesterone into a compound that was readily converted to cortisone.  The ability to cheaply synthesize large quantities of cortisone from the diosgenin in yams resulted in a rapid drop in price to US $6 per gram, falling to $ per gram by 1980. Percy Julian's research also aided progress in the field.  The exact nature of cortisone's anti-inflammatory action remained a mystery for years after, however, until the leukocyte adhesion cascade and the role of phospholipase A2 in the production of prostaglandins and leukotrienes was fully understood in the early 1980s.