Why do i get reoccuring canker sores?

Canker Sores: Canker sores are due to herpes simplex virus type 1. It is very very common. A ton of things can cause recurrent outbreaks. You can buy over-the-counter treatment or see your primary doctor who can prescribe as needed tablets for outbreaks or might opt to put you on daily suppressive therapy. Hsv-1 is painful and unsightly, but don't worry because stress only makes them happen more often.

Stress: At your age, stress and/or hormonal changes are the probable causes. Chart when you get them and see if they coincide w/ your period, or others stresses such as exams, etc.

You are susceptable: Basically, once you get canker sores, you will occassionaly get them again. This autoimmune lesion is set off by various triggers, stress, or trama. Some triggers could be foods(peanuts, spicy food), drinks (red wine), or a cold. It varies with the individual.