Those cold sores are most likely from your mouthpiece. I clean my driptips about every night. When you think about how nasty the human mouth is and how often your mouth is on the driptip, you can understand how bacteria could thrive. Its kind of like using the same fork for weeks without washing it. I use antibacterial dish liquid and wash the drip tip in the palms of my hands. Like i am washing my hands with the driptip in the middle. Once i got into the habit of doing this every night or so, I haven't had a cold sore since.
You don't want to constantly rinse your mouth with a peroxide solution for long periods of time because it will kill the good bacteria in your mouth and give the bad bacteria a clean slate to thrive. Could actually be counter-productive if you use it for weeks and weeks. Clean your drip tips on a regular/daily basis and you wont have any problems.
regard what mentioned by gchirki
i think its logic reason and also i suffered from that may be 4 times in past 5 months,
also its called Aphthous ulcers :its an small, painful ulcers on the inside of the mouth, lips, or throat,
They are small, round, or oval, and are less than 10 mm across. They look pale yellow, but the area around them may look swollen and red. Only one ulcer may develop, but up to five may appear at the same time. Each ulcer lasts 7-10 days, and then goes without leaving a scar.
require no treatment and resolve on their own,just to help relieve pain and speed healing, treatments include topical medications, mouthwashes.
and one of the best past called ((
Solcoseryl Dental Adhesive Paste 5 g.)), also that ulcer can be initiated with over stress and emotional disturbances, i think it can initiated from over heat sensation during vaping with regular Ego batteries as it drop in charge and you vape stronger and longer to get satisfaction vape , this is my experience ,
hope it help others.