Formulation and stability of a beclomethasone dipropionate enema

A beclomethasone dipropionate (BDP) enema and a BDP/mesalazine combination enema (containing 2 mg BDP and 1 g mesalazine and 2 mg BDP, respectively per 40 ml) were formulated. BDP and mesalazine were suspended in a carbomer-water gel. No degradation of BDP was measured during the storage period of the BDP enema (4 weeks at 20 degrees C) and of the BDP/mesalazine enema (44 days at 4 degrees C, 20 degrees C and 37 degrees C, respectively). Progressive darkening of colour occurred for the BDP/mesalazine enema during storage at 20 degrees C and at 37 degrees C, probably induced by mesalazine degradation products. Only very slight colouring was observed at 4 degrees C. Hardly any precipitation of BDP and mesalazine was seen during the storage period and the enemas could easily be resuspended.