The effect of additives on the oral mucosal absorption of human calcitonin in rats.

The oral mucosal absorption of human calcitonin (HCT) was investigated in rats. Enhanced absorption of HCT was observed by coadministration of additives such as sodium deoxycholate, sodium tauroglycocholate, quillajasaponin (Quillayannin P-20), sodium lauryl sulfate, sodium myristate and sugar esters. The contribution of sugar esters to oral mucosal absorption of HCT was studied in some detail. The addition of a sugar ester having a hydrophilic-lipophilic balance value between 11 to 16 was found to be effective in increasing the absorption of HCT. Furthermore, it suggested that the type of constituent fatty acid of sugar ester was one of several important factors for the promotion of the oral mucosal absorption of HCT.