Bladder instillation of verapamil as a means of enhancing the efficacy of chemotherapy in superficial bladder carcinoma: influence of bladder instillation of verapamil on the cardiovascular system
Yoshida, K.; Takahashi, T.; Nakame, Y.; Saitoh, H.; Horiuchi, S.; Kaneoya, F.; Negishi, T.
Gan to Kagaku Ryoho. Cancer and ChemoTherapy 14(2): 506-510
1987
ISSN/ISBN: 0385-0684 PMID: 3813578 Document Number: 291409
Although it is well known that calcium antagonists in vitro possess enhancing effects on anti-tumor drugs, their clinical use is limited on account of side effects on the cardiovascular system. In the present study, the authors attempted the instillation of Verapamil (calcium antagonist) combined with anti-tumor drugs into the bladder for the treatment of superficial bladder carcinoma. The dosage of Verapamil necessary for maintaining an effective concentration for enhancement of the anti-tumor drug was determined and the influences of bladder instillation of Verapamil on the cardiovascular system and on the bladder were studied. The results obtained were as follows: the use of 5 mg of Verapamil was able to maintain an effective concentration (10(-5) M) for enhancement of anti-tumor drugs for at least 2 h. Absorption of Verapamil from the bladder to the vascular system was minimal. No influence on the cardiovascular system or on the bladder was observed. The results of the present study encourage us to pursue the clinical use of Verapamil combined with anti-tumor drugs for the treatment of superficial bladder carcinoma.