Double-blind clinical study reveals synergistic action between alpha-hydroxy acid and betamethasone lotions towards topical treatment of scalp psoriasis.
OBJECTIVE
A double-blind, single-site, split-face clinical study was organized and carried out in order to evaluate the efficacy, tolerability, and safety of a glycolic acid containing scalp lotion in conjunction with a betamethasone (as the 17-valerate) scalp application against conditions of psoriasis.


BACKGROUND
Alpha-hydroxy acids (AHA) have been proposed as therapeutic modalities against skin exfoliative conditions such as ichthyosis, xeroderma, and psoriasis. AHAs are hereby clinically investigated as therapeutic modalities adjuvant to corticosteroids in order to diminish systemic and topical adverse side-effects most frequently associated with use of the latter.


METHODS
Twenty patients suffering from scalp psoriasis and other psoriatic conditions were included in a double-blind, split-face clinical study, using combinations of a 10% (w/w) glycolic acid scalp lotion, placebo lotion (excipients only), and a 0.1% (w/w) betamethasone scalp application, applied twice daily without any bandage for a period of 8 weeks. Clinical assessments were carried out by highly experienced physician evaluations based on a four-grade scale, prior to treatment and after 2, 4, 6 and 8 weeks.


RESULTS
Improvement was observed in all cases included in the study following treatment with the 10% glycolic acid lotion. However, when equal parts of the 0.1% betamethasone lotion were combined, most of the treated sites were healed. Moreover, the duration of treatment required for healing was in this case reduced to approximately half of that needed when the glycolic acid or the betamethasone lotions were used separately for treatment.


CONCLUSIONS
The present clinical study demonstrates for the first time that the effective and well tolerated therapeutic efficacy of glycolic acid scalp lotions is enhanced when used in conjunction with a 0.1% betamethasone scalp application against scalp psoriasis. This potential offers the practising dermatologist with novel treatment modes against severe skin conditions by combining topical corticosteroid with exfoliative agent therapy.
Kostarelos
K
K
Research and Development Section, Farmeco Co., Athens, Greece.
Teknetzis
A
A
Lefaki
I
I
Ioannides
D
D
Minas
A
A
D000287:Administration, Topical; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use*; D001624:Betamethasone Valerate / Q000627:therapeutic use*; D004304:Dosage Forms; D004311:Double-Blind Method; D004357:Drug Synergism; D005938:Glucocorticoids; D006016:Glycolates / Q000627:therapeutic use*; D006801:Humans; D019344:Lactic Acid / Q000627:therapeutic use*; D004364:Pharmaceutical Preparations; D011565:Psoriasis / Q000188:drug therapy*; D012536:Scalp Dermatoses / Q000188:drug therapy*
D000893:Anti-Inflammatory Agents; D004304:Dosage Forms; D005938:Glucocorticoids; D006016:Glycolates; D004364:Pharmaceutical Preparations; C031149:glycolic acid; D019344:Lactic Acid; D001624:Betamethasone Valerate