Disclosed herein are novel methods for reducing or preventing the harmful effects of solar radiation on skin. Also disclosed are novel sunscreen compositions comprising thaizolium, thiadiazolium or triazolium compounds or derivatives and analogs thereof for reducing or preventing the harmful effects of solar radiation on skin. Sunscreen active agents that provide UV-A and UV-B filters are also included. The invention further discloses additional sunscreen active agents, emollients, humectants, dry-feel modifiers, waterproofing agents, insect repellants, antimicrobial preservatives, antioxidants, chelating agents, fragrances and moisturizers, suitable carriers for topical application and emulsions.