3.4.4. UVR Exposure: This procedure involves exposing four 6mm areas of skin over increasing doses of simulated solar radiation (SSR), while the rest of the body is draped. SSR is delivered by a 1,000-Watt xenon arc lamp, which emits ultraviolet wavelengths from 290-400 nm, closely resembling natural sunlight. The sites to be exposed will be dosed as follows: 1 MED, 2 MED, 3 MED, 3 MED. Two sites will be exposed for this study, one before study medication dosing and one after study medication dosing.