The betulin (BE) based triterpene extract (TE) from birch cork contains 81% BE, betulinic
acid (4%), lupeol (3%), erythrodiol (1%) and oleanolic acid (1%). The TE is able to
stabilize a W/O emulsion (BE emulsion) of water and jojoba oil without any other additives
[1]. Experimental studies suggest that the TE components induce anti-inflammatory
[2] and wound healing effects [3] in the skin, but no antipruritic activity is published,
yet.
An open-labelled trial aimed to investigate the antipruritic effects of the BE emulsion.
23 patients with chronic pruritus on unchanged skin as well as 20 patients with pruritus
and chronic scratch lesions received the BE emulsion. It was applied for a period
of two weeks twice daily on the affected areas followed by 2 weeks without cream and
a follow-up visit. Before and after therapy, patients received a detailed clinical
investigation with documentation of present scratch lesions assessed by the prurigo-score.
For daily documentation of pruritus intensity patients used the visual analogue scale
(VAS) from 0 to 10. Statistical analysis was done by intention-to-treat analysis.
A significant antipruritic effect was documented in 56.2% of patients of group 1 and
70.0% of patients of group 2. The dynamic score (reduction of pruritus intensity in
percent) in responsive patients was 66.8% in group 1 and 82.7% in group 2. The analysis
of the VAS data before and after therapy showed a 2.6-fold better response of group
2. Patients of group 2 showed a slight regression of scratch lesions within two weeks
of cream application. Nearly all patients (95.3%) tolerated the therapy well.
The present results suggest that the topical use of TE within a BE emulsion is an
effective, adjuvant antipruritic treatment option with good compatibility in patients
with chronic pruritus, especially in patients with chronic scratch lesions.
References: [1] Daniels, R. (2008) Pharm. Ztg. 11:34–35.
[2] Alakurtti, S. (2006) Eur. J. Pharm. Sci. 29:1–13.
[3] Harish, B.G. (2008) Phytomedicine 15:763–767.