[Iontophoresis of forced skin absorption of indomethacin and salicylic acid].
Cutaneous absorption of ionized substances is forced by iontophoresis. This was shown by Pratzel and Hillmeier's investigation of the permeation of salicylic acid (increasing factor 150) and Pratzel and Dittrich's experiments with indomethacin (factor 10) in pigs. In the present paper it is shown that in human volunteers iontophoretic application of indomethacin for one hour onto the skin of the back (surface 1380 cm2) increased indomethacin plasma levels after 2 hours to a maximum of 221 ng/ml, and increased urinary excretion of indomethacin from 24 micrograms (control) to 138.7 micrograms in 5 hours. Iontophoretic application of salicylic acid for one hour daily in human volunteers onto a skin area of 400 cm2 increased serum levels in five days to 690 ng/ml and urinary excretion of salicylic acid and salicyluric acid to 24 mg, as opposed to 2.5 mg by control without current. However, after 30 min iontophoresis only 4 mg is excreted in the urine. In conclusion, if the iontophoresis is practised over a long period of time on large skin areas, systemic effects can be expected.
D000287:Administration, Topical; D002463:Cell Membrane Permeability; D006801:Humans; D007213:Indomethacin / Q000378:metabolism*; D007478:Iontophoresis; D012459:Salicylates / Q000378:metabolism*; D020156:Salicylic Acid; D012869:Skin Absorption
D012459:Salicylates; D020156:Salicylic Acid; D007213:Indomethacin
Iontophorese zur forcierten Hautresorption von Indometacin und Salicylsäure.