I'm the only one that uses my toothbrush. but i can't afford to buy more. but i get cold sores. is it possible for me to clean it? to kill it on the t

A few thoughts...: 1) Soak it in antibacterial mouthwash 2) Soak it in hydrogen peroxide 3) Boil it for 3 minutes. A generic new toothbrush would cost about 99 cents at your local pharmacy. Bristles tend to wear out, so it is a wise idea to change the toothbrush every so often.

Buy a toothbrush: You can find the $. Colgate sells a pack of 12 for $7.50 which will last about 3 years. Cold sores are another question. They are not influenced by your toothbrush. If you have herpes you can take a dose of valacyclovir 2 Gram[ 2 pills] at the first tingling [prodrome] to reduce the severity and duration of an episode.

See below: It is cheaper to purchase a new toothbrush at a 99 cent store, than deal with specialized sterilization techniques. See your dentist and they will be happy to supply you with a new toothbrush.