Influence of the timing of ultrasound application on the penetration of corticosteroids.
BACKGROUND
The application of ultrasound to enhance the transdermal transport of drugs is often referred to as 'sonophoresis'. In physiotherapy sonophoresis is applied to the skin through two different procedures: (1) the pre-treatment procedure where the skin is treated with ultrasound irradiation prior to the drug application and (2) a simultaneous treatment mode, where the skin is treated with ultrasound during the application of the pharmacologic substance. The aim of this study was to compare the bioavailability of halcinonide in the stratum corneum comparing the ultrasound pre-treatment vs. the simultaneous treatment method.


METHODS
The effect of pre and simultaneous ultrasound treatment (1 MHz, 1 W/cm(2)) was evaluated on the halcinonide blanching response using tristimulus colorimetry 2 h after the initial application.


RESULTS
Within the evaluation period, only the ultrasound pre-treatment method resulted in a significant blanching response.


CONCLUSIONS
Timing of the ultrasound application seems to influence the availability and percutaneous penetration process and should be taken into account when estimating the ultrasound enhancing effect.
Faculty of Physical Education and Physiotherapy, Vrije Universiteit Brussel, Brussels, Belgium. r.clijsen@physioschule.ch
R
R
Clijsen
J P
JP
Baeyens
A O
AO
Barel
P
P
Clarys
D000279:Administration, Cutaneous; D000305:Adrenal Cortex Hormones / Q000493:pharmacokinetics*; D000328:Adult; D000893:Anti-Inflammatory Agents / Q000493:pharmacokinetics; D016503:Drug Delivery Systems / Q000379:methods*; D004817:Epidermis / Q000000981:diagnostic imaging* / Q000378:metabolism*; D005260:Female; D006206:Halcinonide / Q000493:pharmacokinetics*; D006801:Humans; D008297:Male; D012869:Skin Absorption; D014465:Ultrasonics / Q000379:methods*; D014463:Ultrasonography; D055815:Young Adult
D000305:Adrenal Cortex Hormones; D000893:Anti-Inflammatory Agents; D006206:Halcinonide