Cold sores are caused by the herpes simplex virus (simply known as HSV), usually the type 1 strain (HSV-1), while HSV-2 is the one typically responsible for genital herpes, although it should be noted that both types can cause either oral or genital herpes, it’s just that one particular strain more commonly causes one particular manifestation of the disease than the other. Cold sores cycle between active and dormant periods–the dormant period is the state the virus is in 95% of the time, and during this time it is basically hibernating in the nerve cells of the face, where it remains forever (sorry, you can’t ever get rid of herpes–there are currently no known cures, although vaccines to prevent infection are in the works). The active outbreak period, where you actually have a cold sore you can see, lasts for between 2 and 21 days.The odd thing is that contracting herpes causes an immune response called seroconversion from the body which releases antibodies to that specific strain of HSV which will thereby prevent an infection by that strain at any other site in the body–if you get oral herpes that means you are now immune to and cannot get herpes whitlow, herpes keratitis, or herpes encephalitis. It’s also been shown that exposure to HSV-1 (i.e. in the form of oral herpes) seems to reduce the symptoms of a later HSV-2 infection (i.e. genital herpes), and most indications are that an HSV-2 infection will immunize that person against HSV-1, so if you get genital herpes odds are very good that you’re now immune to and cannot get oral herpes.There are a great many cold sores remedies out there, some more valid than others, and through my own experience the best of these are as follows:Lysine: It’s been proven in multiple scientific studies that lysine not only reduces the length and severity of a cold sore outbreak if you take it while you have a cold sore, but if you take it regularly even when you don’t have a cold sore it will reduce the total number of active outbreaks (cold sores) you’ll get over time (Source: Indiana University School of Medcine, see: ncbi.nlm.nih.gov/pubmed/3115841)Benzyl Alcohol (aka Zilactin): this is one of the few home remedies recommended by the Mayo Clinic (Source: mayoclinic.com/health/cold-sore/DS00358/DSECTION=treatments-and-drugs)–what you do is just apply a little bit of it to your cold sore with a q-tip once every few hours (I would say once every 2-3 hours is good).Ice: this is an obvious but commonly overlooked one–not only does it reduce the pain and itching, but it also, by many accounts including my own, reduces the severity and duration of the outbreak by slowing the replication of the virus.Witch Hazel: I see this one recommended a lot, even more than the benzyl alcohol, and I’ve tried it myself and found it to have a similar effect but not quite as good–use if you can’t find any benzyl alcohol, it works as a substitute.Nail Polish Remover: what you do is put some on a q-tip and apply it last after you’ve washed the cold sore, iced it, put benzyl alcohol or witch hazel on it, and whatever else you want to do with it. It keeps the cold sore completely dried out by sucking up all the fluid that (nasty yellowish stuff) that’s normally produced by the sore. I’ve found this to be very effective at doing this, and keeping that fluid out of there is really, really important as far as getting rid of your cold sore is concerned.