Before applying in wider area, there must be a test in a smaller area like elbow skin. If there’s a feeling of heat, itchy and a rash, stop using it immediately. To maximize the using of Kemenyan, there will be a dose that people should know. Basically, every dose of herb is different including Gum Benzoin Sumatra. It really depends on the age, health and other conditions. For further actions, it is advised to consult with herb expert for maximum result.