The therapeutic effect of topical Hydnocarpus anthelminthicus oil in combination with 0.1% triamcinolone acetonide in psoriasis; A Randomized Control Trial

Abstract

Background: Hydnocarpus anthelminthicus, krabao in Thai, a herbal medicine, has been used mainly for the treatment of leprosy. Oil extracted from its seeds “chaulmoogra oil ” administered orally shown an anti-inflammatory and anti-nociceptive activities in animal model. Psoriasis is a chronic inflammatory disease which involves multiple immune mechanisms which cause abnormal keratinocytes proliferation and differentiation. Chaulmoogra oil has been used in Thai herbal remedies for psoriasis but its efficacy has never been elucidated.

Objectives: to determine whether topical chaulmoogra oil can enhance the efficacy of topical steroid in the treatment of psoriasis.

Materials and methods:  Randomized double-blinded intra-individual control trial was conducted in 27 patients with symmetrical stable chronic plaque type psoriasis. Half-body lesions were randomized to treat with topical 0.1 percent o/w triamcinolone acetonide in chaulmoogra oil or 0.1 percent o/w triamcinolone acetonide in mineral oil, which served as control, twice daily for 4 weeks. Local psoriasis severity index and physician’s global assessment were evaluated at baseline, and at the second and fourth week by investigators and photographs. Patient satisfaction was evaluated at the last visit.

Results: 24 patients completed the study. Both 0.1 percent o/w triamcinolone acetonide in chaulmoogra oil and control regimen significantly reduced erythema, thickness and scales of index lesions (p-value < 0.0011,p-value= 0.0038 and p-value= 0.0038, respectively). In contrast, the mean difference in areas of index lesion after treatment was significantly increased in the chaulmoogra oil treated side. However, after combining all parameters, the PASI score reduced significantly from the baseline on both side (p-value =0.0001).There were significant improvements of physician’s global assessment and visual analogue scale of itchiness and irritation in both sides. Overall satisfaction scores of the treated group and the controlled group were not significant difference, 6.87(±2.10) and 7.30(±1.93), respectively   (p-value = 0.12).

Conclusion: 0.1 percent o/w triamcinolone acetonide in chaulmoogra oil or in mineral oil demonstrated similar efficacy in term of erythema, thickness scales and reduction of psoriatic index lesions. The effect of triamcinolone acetonide in chaulmoogra oil preparation was not superior to the standard preparation of 0.1% triamcinolone acetonide cream.