A novel ointment base suitable for the treatment of bedsore at the recovery stage was developed by the use of hydroxypropyl methylcellulose (HM-HPMC) modified on the basis of the hydrophobicity. A considerable sustained release of drug (minocycline hydrochloride) formulated to the ointment (T50 of 170 min) was attained with a macrogol ointment (MO) mixed with the HM-HPMC and Carbopol (CP) of the formulating ratio of 3:7. It was also found that a change in the formulating ratio of HM-HPMC and CP lead to a change in the drug release rate. The water absorption property of the ointment base, required to absorb on exudative solution in applying to the bedsore treatment, was as high as that of an ointment base containing hydroxypropyl cellulose (HPC) and CP reported in our previous paper. We clinically evaluated the effectiveness of the bedsore treatment, in which different ointment bases were applied to patients at different stages of the bedsore. A total of 22 cases were divided into two categories for applying to the different treatments. One category comprised of 11 subjects was treated with a povidone-iodine sugargel, which was the conventional method in our hospital, while the other 11 subjects were treated by the use of the newly developed ointment bases in consideration for the different stages of the bedsore. In comparison of the clinical results with the healing index, we ascertained that the latter method was significantly more efficacious (p<0.01-0.05) than the conventional one. The effectiveness was emphasized in treating the intractable bedsore classified into the grades IV and V. Therefore, we confirmed that the newly developed ointment base formulation is useful in treating bedsore at each stage.
