The changes of the barrier function of axillary skin and the quality of life in the patients of axillary hyperhidrosis after the injection of botulinum toxin A

Background: Axillary hyperhidrosis is a distressing problem in the making of a person's social life. The characteristics of the axillary skin in the patients of the axillary hyperhidrosis and the exact reasons of the reduced barrier function of the axillary skin are still not known. Objective: To confirm the changes in the barrier function of axillary skin and the changes in the quality of life, before and after, the injection of botulinum toxin type A for patients of primary axillary hyperhidrosis. Methods: The subjects of this study, were composed of nineteen patients of primary axillary hyperhidrosis. The values of hydration (Corneometer), transepidermal water loss (TEWL) and acidity (pH) on the skin of the axilla and forearm were measured, each time before and at 1 week, 2 weeks, 3 weeks, 4 weeks, and 3 months after the injection of botulinum toxin A. The changes in the quality of life were also measured, through the Modified Dermatology Life Quality Index (MDLQI), before and at 4 weeks after the injection of botulinum toxin A. Results: Compared with the skin of the forearm, the values of the Corneometer, TEWL, and pH were significantly higher in the axillary skin. Also the values of the Corneometer, TEWL, and pH decreased after the injection of botulinum toxin A, reaching the lowest levels, in all parameters, at 3 weeks. The quality of life improved significantly, with the MDLQI decreasing from 18.63 to 4.53. Conclusion: It can be suggested that the reduced barrier function in the axillary skin is associated with the increased activity of the eccrine gland of the axilla, so it is, at least, partially recovered by the inhibition of sweating through the botulinum toxin A injection. Furthermore, the quality of life for patients of axillary hyperhidrosis can be significantly improved by the injection of botulinum toxin A.