REVIEW OF OVER-THE-COUNTER TOPICAL ANALGESIC PRODUCTS AVAILABLE IN AUSTRALIA

Over-the-counter (OTC) topical analgesics are widely available in Australia and can be purchased without a prescription. These products are typically marketed as treatments for arthritic pain or muscle soreness. There is currently no literature examining the active compounds/botanical extracts usually incorporated in these products, especially relating to products which have not been independently assessed for efficacy by the Australian Therapeutic Goods Administration (TGA). This review aims to highlight the active ingredients commonly incorporated in OTC pain products available for purchase in Australia and assess the literature relating to their efficacy and mechanisms of action. Most of the active ingredients in these analgesic formulations are natural products or plant extracts/essential oils. The most cited active ingredient is Arnica montana despite the lack of conclusive evidence that this plant is efficacious in treating pain when administered topically. The mechanisms for pain relief in the products are mainly transient receptor potential channel agonism, or rubefacient/counterirritant effects, with other products exhibiting cyclooxygenase antagonism. The most common ingredients in TGA registered products are the natural products menthol, methyl salicylate, Eucalyptus oil and camphor.