2 Answers

Hormonal changes?

This link has everything you need to know about cold sores associated with your period. I would copy and paste it to answer but there's too much. http://www.associatedcontent.com/article…
As for cold sores and herpes; They are the same thing, cold sores can be caused by oral herpes and also known as HSV1. It can be easily passed just by some one with cold sores giving you a kiss. They can even be passed when your a child when a relative or friend with cold sores gave you a kiss or you shared some thing like utensils, chap stick, or cups with them. They can be triggered by stress, extreme cold weather, prolonged exposure to sunlight, even certain foods can trigger a sore. That is usually how cold sores start off. You can use over the counter creams like Abreva or Lipactin to help heal them. Also don't kiss or give your boy friend oral sex. Cold sores are very contagious and can be easily passed on while they are active. Cold sores are extremely common to have 50-80 percent of the world has them.

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Student nurse