PROLONGATION OF ANTIDIURETIC RESPONSE TO DESMOPRESSIN ACETATE BY IONTOPHORETIC TRANSDERMAL DELIVERY IN RATS

An iontophoretic drug delivery system was compared with intranasal, or al and subcutaneous delivery from a standpoint of the prolongation of the antidiuretic response to desmopressin acetate (DDAVP) in diabetes insipidus rats. Iontophoretic delivery was comparable to the nasal rou te at a dose about five times higher than the nasal route dose, and wa s 2 to 3 times as effective as the oral route. Effect of dose and dura tion of current application on the prolongation of the response to DDA VP was also investigated in order to find the effectiveness of the ion tophoresis. The antidiuretic response to DDAVP delivered by iontophore sis indicated a dose-dependent prolongation and,vas prolonged up to ab out 14 h with the increase of the duration of current application; whe n a pulsed direct current at 0.1 mA was passed for about 1 h, the resp onse to DDAVP was prolonged for about 9 h. DDAVP in the anodic donor s teeply decreased with the application for I h, and then gradually decr eased. We suggest that the antidiuretic response to DDAVP can be effec tively controlled by regulating the absorption of DDAVP at the short-t erm iontophoresis rather than prolonged treatment.