The purpose of this study is to determine the amount of substances contained in skin known as microvesicle particles (MVP). Studies suggest these MVP are involved in many conditions such as after the thermal burn injury. These particles are typically found in skin and are evaluated by taking a portion of area with skin biopsy. The hypothesis to be tested is that people treated with a small burn injury will result in MVP levels and that this can be blocked by applying the drug amitriptyline to the area. The topical amitriptyline will be given either immediately after the burn, or at a short time afterwards (5 or 15 minutes). Skin biopsies of the areas will be taken and the study team will measure the MVPs in the skin. By utilizing these methods the study team can determine if there are differences in the numbers of MVP made following a small thermal burn injury and if this can be blocked by topical treatment with amitriptyline.