Cochrane: Acne is a chronic
skin disease, which causes spots to occur simultaneously on several
areas of the body, including the face, neck, back, and chest. Besides
the current commonly used treatments, complementary and alternative
medicines (CAM) are of increasing interest to people who often use them
in addition to conventional treatments as additive or single therapies
to treat acne.
The review question
Can any complementary therapies improve the clinical symptoms of acne vulgaris?
Study characteristics
We searched relevant databases and trials registers up to 22 January
2014. We identified 35 randomised controlled trials, with 3227
participants, which used 6 kinds of CAM (herbal medicine, acupuncture,
wet cupping, diet, purified bee venom, and tea tree oil). A
pharmaceutical company funded one trial; the other trials did not report their funding sources.
Key results
For our primary outcome,
we combined two studies that compared a low- with a high-glycaemic-load
diet (LGLD, HGLD), but found no clear evidence of a difference between
the 2 groups at 12 weeks for a change in non-inflammatory lesion counts. Only one of these two trials provided usable data to show potential benefit of LGLD for reducing inflammatory and total skin lesion counts. Tea tree oil and pollen bee venom were found to reduce total skin lesion
counts in single trials, respectively. The remaining 31 included trials
gave mixed results about whether complementary therapies might reduce
the total number of skin lesion counts.
Twenty-six trials reported adverse events. The herbal medicine group
found some mild side-effects, such as nausea, diarrhoea, and stomach
upset. The acupuncture group found some itch or redness and pain
following needle insertion. Participants who used tea tree oil reported
itchiness, dryness, and flaking of the skin. None of the trials reported
severe adverse effects.
For our secondary outcome,
there was no clear evidence of a difference in the number of
participants with remission between Ziyin Qinggan Xiaocuo Granule and
minocycline according to a meta-analysis of two studies.
Quality of the evidence
There is some low-quality evidence from single trials that a
low-glycaemic-load diet, tea tree oil, and bee venom may reduce skin
lesions in acne vulgaris, but there is a lack of evidence from the
current review
to support the use of other CAMs. Methodological and reporting quality
limitations in the included studies weakened any evidence.