Xerosis is a major cause of pruritus, particularly in climates with low humidity or cold temperatures and in older persons. When skin is extremely dry, excessive flaking of corneocytes can cause the formation of microfissures and an increase in mast cells and histamine levels, which results in chronic itch.1,2 Although many available topical products can provide patients with moisturizing benefits, few well-controlled clinical studies have been conducted that demonstrate significant benefits of specific active compounds.3,4,5 We performed a randomized, controlled clinical study to address this deficiency in the literature. We aimed to compare the moisturizing abilities of the active ingredient in a commercially available colloidal oatmeal skin protectant with its vehicle lotion.
This study was approved by the Mayo Clinic Institutional Review Board. Patients seen in the Department of Dermatology, Mayo Clinic, Rochester, Minnesota, were recruited to participate in the study between December 2011 and April 2012. Thirty women aged 18 to 70 years with bilateral moderate to severe xerosis and bilateral mild to moderate pruritus on the lower legs were enrolled. All patients who agreed to participate provided informed consent. For all potential subjects, the skin on their lower legs was clinically graded at a preliminary visit. Eligible subjects needed to have bilateral moderate to severe dryness (scores of 2-4 on a 0-4 skin dryness scale) and bilateral mild to moderate itch (scores of 1-2 on a 0-3 subjective itching scale) on both lower legs. Subjects were excluded from the study if they had active dermatitis or other skin disease involved on their legs.
All enrolled subjects were instructed to refrain from using any leave-on products on their lower legs for the 5 days before the start of the study. During the first study visit (baseline, day 0), each subject was assigned to use both test products in a bilateral study design: one product labeled as â€œA,â€ to be used on the right leg, and the other labeled as â€œB,â€ to be used on the left leg. The 2 test products were a commercially available skin relief moisturizing lotion with colloidal oatmeal skin protectant (Aveeno Skin Relief Moisturizing Lotion, Johnson & Johnson CCI) and its matching vehicle lotion (provided by Johnson & Johnson CCI). Both the subjects and the clinical investigator were blinded as to the identity of products â€œAâ€ and â€œB,â€ which was randomized for each patient. Subjects were instructed to apply the products to the lower legs twice daily and continue with this application regimen for 3 weeks, then discontinue all treatments for 1 more week.
Test sites on the lower legs of each of the subjects were graded clinically by the author (A.N.K.). Grading was done at baseline (day 0), after 21 days of treatment, and after a 1-week regression period without treatment (day 28). Scaling and cracking of the skin were graded on a scale of 0 (no scaling or cracking) to 9