Cold sores / herpes simplex are caused by a virus that lives in your body and manifests itself from time to time as a small cluster of outbreaks. These are contagious. While the breakouts are unpredictable, certain factors can trigger their onset / occurrence. These include stress, minor infections, sun exposure, and foods like chocolate or nuts. What can you do? A strong immune system is vital to preventing outbreaks. Specific ingredients are known to bolster immune factors which suppress the outbreaks. Numerous studies in publications such as Dermatologica and the Journal of Medical Virology have shown the effectiveness of the amino acid lysine. Applying the cream at the first sign of tingling or outbreak can halt the outbreak or make it disappear quickly. The cream will also soothe and relieve painful outbreaks. If you have infrequent, and minor outbreaks, the cream may be all you need.