Topical use of 0.05% Oxymetazoline hydrochloride solution (nasal decongestant) is effective, well-tolerated, and safe for reducing post-acne erythema without a rebound effect.

Post-acne erythema (PAE), which is a common result of acne inflammation, poses a significant challenge for effective topical treatment. This study aimed to assess the safety and efficacy of a 0.05% solution of Oxymetazoline hydrochloride (OxH) in managing PAE.

The investigation was performed as a randomized, placebo-controlled trial. Eligible participants included healthy adults (age 18 to 45 years) suffering from mild to severe PAE on both sides of their face, as determined by the Clinician's Erythema Assessment. During the 12-week study period, the recruited subjects applied OxH to one side of their face and a placebo to the other side, twice daily.

In this split-face, double-blind study, the key endpoint ascertained was the count of PAE lesions, while secondary endpoints encompassed the erythema index, satisfaction scores of patients, and clinical response rate at week 12 (assessed as "clear," "almost clear," or "minimum 2-grade improvement" by Clinician's Erythema Assessment).

Overall, 30 volunteers were recruited. Following eight weeks, the OxH-treated skin exhibited a remarkably greater decrease in PAE lesion counts when compared to the placebo (mean difference: 4.30). Similarly, from the second week onwards, the OxH-treated skin illustrated a higher decrease in the erythema index (mean difference: 11.82).

Furthermore, the OxH-treated side exhibited a higher clinical response rate at eight weeks (40.00% vs. 6.67%) and better patient satisfaction at the end of the trial (mean [standard deviation] satisfaction score: 8.30 [0.18] vs. 7.40 [0.18]) compared to the placebo. No severe adverse events or erythema flares were witnessed.

Topical application of a 0.05% solution of OxH effectively reduced PAE without any rebound effect, while also being well-tolerated and safe. Therefore, it could be considered a viable therapeutic option for managing PAE.