Blister-like bumps on my Runner's bill?? Help!!

[Miss Lydia]

Is this area like a blister with fluid in it?

 

[crazyrun]

Yes it is. Does not seem to be causing any pain. Just noticed it at the beginning of the week. The mouth looks clear. Not seeing any cuts or scrapes.

 

[Miss Lydia]

I've seen this before but have no idea why it happens. And not sure if it should be left alone or had something done to it. If it's not causing pain and he is doing all things natural like eating and drinking might just be best to watch it.