how do you tell if its a canker sore or herpes

you should go to the dr and let them determine.

Canker sores r inside ur mouth & cold sores r on ur lips or sometimes face. So if it is inside ur mouth it is not a cold sore - it may not be a canker sore either, as there r other things that can cause sores inside ur mouth. Cold sores r contagious & canker sores r not. Cold sores r caused by the herpes virus, while scientists r not really sure what causes canker sores.

Numerous factors have been associated with canker sores, & what causes them in any individual case is often hard to figure out. They r one of those disorders that r not well understood.

Canker sores will get better on their own without any treatment. But there r things u can do to help it along & to feel better. Orajel & Anbesol, both of which u can get without a prescription, will numb the sore & make it less painful. There r also prescription medications u can get that will help. There r several mouthwashes that can help – look for one without alcohol. Even if u don’t have any of those treatments, u can rinse ur mouth with warm salted water several times a day. It is gross, but it will help.

These sites give the details about canker sores & how to treat them.

http://kidshealth.org/teen/diseases_conditions/mouth/canker.html
http://medicinenet.com/canker_sores/article.htm
http://wikihow.com/Treat-Canker-Sores-or-Mouth-Ulcers
http://webmd.com/skin-problems-and-treatments/tc/canker-sores-topic-overview

If u think u have a cold sore, u should see ur doctor about a prescription for an anti-viral medication. Here r a couple of good links about cold sores.

http://webmd.com/skin-problems-and-treatments/tc/cold-sores-topic-overview
http://kidshealth.org/kid/ill_injure/aches/cold_sores.html
http://ashastd.org/herpes/herpes_learn.cfm
http://medicinenet.com/valacyclovir/article.htm