Effect of pulsed output ultrasound on the transdermal absorption of indomethacin from an ointment in rats.
The effect of pulsed output ultrasound (1 MHz) with on/off ratios of 1:2, 1:4 and 1:9 on transdermal absorption of indomethacin from an ointment was studied in rats. Ultrasound energy was supplied for between 10 and 19 min at a range of intensities (1.0-2.5 W.cm-2), energy levels commonly used for therapeutic purposes. The on/off pulsed ratio, intensity and the time of application were found to play an important role in the transdermal phonophoretic delivery system of indomethacin; 1:2 pulsed output ultrasound appeared to be the most effective in improving the transdermal absorption. The highest penetration was observed at an intensity of 1.0 W.cm-2 and application time of 15 min. With pulsed output it was possible to use higher intensities of ultrasound without increasing skin temperature or damaging skin.
Asano
J
J
Faculty of Pharmaceutical Sciences, Health Science University of Hokkaido, Japan.
Suisha
F
F
Takada
M
M
Kawasaki
N
N
Miyazaki
S
S
D000279:Administration, Cutaneous; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000493:pharmacokinetics*; D019540:Area Under Curve; D007213:Indomethacin / Q000008:administration & dosage / Q000493:pharmacokinetics*; D008297:Male; D009824:Ointments; D015612:Phonophoresis; D051381:Rats; D017208:Rats, Wistar; D012869:Skin Absorption / Q000528:radiation effects*; D014465:Ultrasonics
D000894:Anti-Inflammatory Agents, Non-Steroidal; D009824:Ointments; D007213:Indomethacin