The inclusion compound of emulsified cetostearyl alcohol withβ-cyclodextrin and a competitive reaction with a hydrocortisone/β-cyclodextrin inclusion compound in an oil-in-water cream

-cyclodextrin can form a solid inclusion compound with emulsified cetostearyl alcohol (ECA) by coprecipitation. This was proved by differential scanning calorimetry (DSC), X-ray diffractometry, IR spectrometry and the determination of the foaming ability according to the German Pharmacopeia (DAB 10) for ECA in the coprecipitate. The DSC result shows that both ingredients, cetostearyl alcohol and cetostearyl sulfate, are included in the-CD cavity. The coprecipitate is therefore a mixture of inclusion compounds. ECA as a constituent of Hydrophilic Ointment (DAB 10) can substitute up to 10% hydrocortisone in Aqueous Hydrophilic Ointment(DAB 10) containing 1% HC as-CD inclusion compound under the conditions of preparation.