Relief for itching: Dihydroavenanthramide D eases pruritus

November 1, 2008

Several ingredients found in topical preparations help treat dry skin and the subsequent symptom of pruritus. The results of a recent study with dihydroavenanthramide D demonstrate the agent is very effective in the treatment of pruritus, and according to one expert, should be considered an option when trying to treat and subdue pruritic symptoms.

Key Points

Teterboro, N.J. - An intractable itch, whatever the cause, can be a source of significant bother and can have a significant psychosocial impact on patients, interfering with sleep and daily activities.

Many avenues of therapy have been attempted to subdue severe pruritus, with varying successes.

However, the results of a recent study show that dihydroavenanthramide D can be very effective in the treatment of pruritus, giving hope to patients suffering from this sometimes debilitating skin symptom.

Time-tested treatment

Oatmeal and oatmeal extracts historically have been used to treat skin itch and irritation. The main active components are avenanthramides, a group of anthranilic acid amines found only in oats at very low concentrations.

Ravi Pillai, Ph.D., director, Life Essentials Scent and Care Division at Symrise, Teterboro, N.J., and colleagues, conducted a recent in vivo study aimed at evaluating the efficacy of a topical preparation containing dihydroavenanthramide D - a synthetic form of the avenanthramides - for dry, pruritic skin.

Study parameters

The four-week, double-blinded, cross-over study included 40 patients, ages 35 to 80 years, who had visibly dry skin and complained of moderate itch.

Half of the patients received an anionic oil-in-water vehicle emulsion alone for two weeks (considered the placebo), and then switched to the same emulsion base with the active 0.10 percent dihydroavenanthramide D added to it for an additional two weeks. The other half received the same therapy in reverse order.

Patients were assessed at weeks two and four for scaling, erythema, excoriation, lichenification and itch.

Results

Results showed that all patients improved on all parameters with dihydroavenanthramide D plus vehicle and vehicle alone.

Dr. Pillai says this was most probably due to the excellent moisturization that the emulsion vehicle gave.

However, all patients did show more of an improvement of dry skin symptoms and pruritus when using the dihydroavenanthramide D plus vehicle than with the vehicle alone.

"Our past studies have shown that dihydroavenanthramide D is effective in reducing the inflammation seen by the release of histamine.

"The results of this study showed that patients did not perceive a difference in their symptoms between placebo and the active ingredient.

"Interestingly, though, patients generally did significantly better in terms of their symptoms when dihydroavenanthramide D was included in the formulation," Dr. Pillai tells Dermatology Times.

Hydration

Proper hydration is absolutely key when treating patients with dry skin.

An ideal vehicle used in any topical product for dry skin must be able to adequately hydrate the skin, which will invariably give the patient an almost immediate sense of relief from the itch. Other agents, such as polidocanol, can also be effective for the treatment of itch due to dry skin, Dr. Pillai says.

In a past study in which Dr. Pillai compared the anti-pruritic effects of dihydroavenanthramide D and polidocanol, avenanthramides were found to be significantly more effective in subduing pruritus, underscoring its clinical value.

Disclosure: This study was sponsored by Symrise.