In healthy adults treated for two weeks with 50 to 800 mcg of ciclesonide nasal spray daily (n=6 in each treatment group), the peak serum concentrations of des-ciclesonide in all subjects were found to be below 30 pg/mL. Of those treated with 800 mcg and 400 mcg daily, 100% and 67% had detectable levels of des-ciclesonide, respectively. With daily doses of 200 mcg or less, detectable serum levels of des-ciclesonide were not observed. The low systemic exposure following ciclesonide nasal spray administration was confirmed in a crossover study in twenty-nine healthy adults. The median C max was less than 10 pg/mL and 602 pg/mL following a single dose of ciclesonide nasal spray (300 mcg) and orally inhaled ciclesonide (320 mcg), respectively.
Clobetasone butyrate % (Eumovate), a halogenated topical steroid, was compared with hydrocortison butyrate % (Locoid) which does not contain any halogen atoms. In the treatment of eczema there was not difference between the preparations, but in that of psoriasis the halogen-containing steriod was significantly more effective. Under normal circumstances neither preparation had any detectable effect on adrenal function, but with large doses under total-body polythene occlusion, circulating cortisol levels were reduced less by the halogenated than by the non-halogenated preparation. Corticosteroids which contain a halogen atom are often considered to cause more adverse effects than the non-halogenated preparations with similar clinical efficacy. This study shows that this cannot be assumed for their ability to suppress cortisol levels.
Corticosteroids have been used as drug treatment for some time. Lewis Sarett of Merck & Co. was the first to synthesize cortisone, using a complicated 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.