Zinc dramatically reduces signs of acne rosacea

Original Internist, March, 2007 by Steve Austin

Design: Randomized double blind crossover clinical trial

Participants: Of 25 rosacea patients, (aged 21-64 years), 19 completed the trial.

Study Medication and Dosage: 100 mg of zinc sulfate (ZnS[O.sup.4]) containing 40 mg Zn was administered three times per day for three months.

Main Outcome Measure: Rosacea severity scores

Key Findings: In the arm that initially received ZnS[O.sup.4] therapy, the mean baseline severity score was 8. (Scores of 5-10 reflect moderate severity, with scores below 5 reflecting mild signs and those above 10 reflecting severe signs.) This number fell to 5.7 at one month, to 3.4 at two months, and to 1.6 at the end of the three-month intervention (p<0.01 compared with baseline).

In the arm that received ZnS[O.sup.4] during the second half of the trial, the mean baseline severity score was 7, which fell to 5.9 at one month, 3.9 at two months, and 1.9 at the end of the three-month ZnS[O.sup.4] intervention (p<0.01 compared with the end of the placebo period).

In both groups, erythema began improving after two months, though papules and pustules showed improvement after only one month. Telangiectasia scores did not improve in either group.

During placebo administration, scores began moving back toward baseline in the group that had initially been assigned to ZnS[O.sup.4], though the mean score had only risen to 2.6 by the end of the third month. In the arm initially assigned to placebo, severity scores increased mildly during the placebo administration.

Practice Implications: In the 1970s and '80s, several trials reported that Zn supplementation aided patients with acne vulgaris. The new report extends those findings to patients with acne rosacea.

The effect was dramatic--an average of approximately a 77% decrease in severity in three months. The mechanism behind the effect remains unclear, though the researchers speculate the Zn might have an effect against demodex mites or other potential pathogens. Alternatively, they suggest that a free radical-scavenging effect of Zn might be responsible.

This trial was conducted in Iraq. Much of the Middle East contains a diet low in Zn, complicated further by the use of phytate-rich unleavened bread, which reduces bioavailability of Zn. Serum Zn levels were not measured in the new report, so it remains possible that the effects observed here were simply the function of overcoming a deficiency that may not exist in western populations. However, there is much overlap between acne vulgaris and acne rosacea, and the earlier reports of positive effects of Zn supplementation in vulgaris patients came mostly from western trials. Thus, a therapeutic trial of Zn supplementation in rosacea patients is now worth consideration. Long-term (three months or longer) Zn administration should be accompanied by supplementation with 1-3 mg per day of copper to prevent a Zn-induced copper deficiency.

Sharquie KE, Najim RA, Al-Salman HN. "Oral zinc sulfate in the treatment of rosacea: a double-blind, placebo-controlled study." Int J Dermatol 2006; 45:857-61.

By Steve Austin, N.D.