INTRODUCTION
Current therapies for acne include topical treatments,
systemic antibiotics, hormonal agents, isotretinoin,
complementary therapies, and other miscellaneous
treatments.1 Excluding benzoyl peroxide preparations, regimens containing salicylic acid (SA) as the active ingredient are
the most widely used. Salicylic acid is thought to work by penetrating into comedones and has mild anti-inflammatory properties and keratolytic effects, leading to desquamation of the epidermis and dermal matrix regeneration.2 Salicylic acid can
optimize the texture and tone of treated skin.3,4
Because of the high side-effect profile of benzoyl peroxide
and resultant poor patient compliance, there is an increased
need for efficacious and tolerable acne products without
benzoyl peroxide. Over-the-counter (OTC) products containing SA are readily available, but clinical evidence supporting
their use is limited. Effective products must have acceptable
safety and tolerability profiles to support long-term usage. In
addition to the active ingredient(s), other components of any
treatment regimen are used to improve long-term usage and
product acceptability.
The investigational regimen used in this study included 0.5%
SA plus up to 2.0% highly purified sandalwood oil from
Australia, a well-characterized botanical product with documented antibacterial, anti-inflammatory, and restorative
properties.5,6 Sandalwood oil has been shown to be an effective
antibacterial against Staphylococcus aureus, Staphylococcus
epidermidis, and Propionibacterium acnes at concentrations
of 0.06% and lower6 (Santalis, unpublished data) and to exert
anti-inflammatory effects mediated by inhibition of cyclooxygenase(COX)-1, COX-2, and 12-lipoxygenase pathways6 and
in lipopolysaccharide-stimulated dermal fibroblast and
keratinocyte models through the downregulation of proinflammatory cytokines and chemokines, including interleukin (IL)-6,
IL-8, epithelial neutrophil-activating peptide-78, macrophage inflammatory protein 1α., granulocyte colony-stimulating factor,
and granulocyte macrophage colony-stimulating factor (Santalis, unpublished data).6 In traditional medicine, sandalwood oil
was used to treat in!ammatory and eruptive skin diseases.7,8
Although many acne treatments are somewhat effective, none is
100% curative. Treatments that have undergone extensive clini-