Intradermal drug delivery:

the field of dermatological research by sonophoresis

M. Nino, G. Calabrò , A. Patalano and P. Santoianni

Dept. of Systematic Pathology - Section of Dermatology - University of Naples Federico II

INTRODUCTION

The skin is an important barrier to the penetration of exogenous

substances and a potential route for the transport of

functional active principles.

Several methods have been studied to increase the penetration

for a systemic or a loco-regional effect.

Sonophoresis is the main physical technique that increases

cutaneous penetration of substances. It is based on 20 to 25

KHz ultrasounds that can induce alterations of the horny

barrier through micromechanical, thermal and cavitation

effects.

MATERIALS AND METHODS

This study evaluated the efficacy of low frequency sonophoresis

(LFS) at 25 KHz produced by a sonicator for treatment of

alopecia areata, melasma and solar lentigo.

30 patients affected by alopecia areata were treated for a 3-

month period by 36 applications (three times a week) of

methylprednisolone 0.5% pet. or cyclosporine 0.1% solution

followed by LFS.

48 women with melasma and 48 with solar lentigo were treated

for a 5-week period by 10 applications (twice a week) with a

depigmenting emulsion based on cogic, azelaico and ascorbic

acid and LFS application.

RESULTS

For alopecia areata the results were: a) with

methylprednisolone, 57% partial and 29% total regrowth

(Figg. 1-3); b) with cyclosporine, 33% partial and 34% total

regrowth (Figg. 4-6).

For melasma: 25% partial and 75% complete depigmentation

(Figg. 7-8).

For solar lentigo: 57% partial and 43% total regression (Figg.

9-10).

CONCLUSIONS

The study shows that LFS is a not aggressive technique,

enhances penetration of topic agents obtaining effects at the

level of the epidermis, dermis and appendages (intradermal

delivery), giving good results in the treatment of some

cosmetic skin disorders.

Figg. 4,5,6: Treatment by cyclosporine + LFS: results in a patient. Before treatment (a), after 1-month treatment (b), after 3-month treatment (c).

ba c

Figg. 1,2,3: Treatment by methylprednisolone + LFS: results in a patient. Before treatment (a), after 2-month treatment (b), after 3-month treatment (c).

Alopecia areata

a b c

Melasma

Figg.7-8: Treatment by emulsion + LFS: results in a patient with melasma. Before treatment and after 5-week treatment.

Solar lentigo

Figg. 9-10: Treatment by emulsion + LFS: results in a patient with solar lentigo. Before treatment and after 5-week treatment.