How to prevent blisters between my third and fourth toes…

If your toes were rubbing against each other, that probably means the shoes are too narrow at the front. Wrong shoes for you.

Cheers

I have only had blisters on my toes when hiking on very dusty trail when my feet get covered in grit. In that case I have been able to avoid those blisters by keeping my feet cleaner.

Toe socks might help, since your toes are rubbing against each other.

I think Roger's idea is good

I have a pair of boots that is too narrow at the front and get blisters on those toes

It's like my feet are more broad at the front but the boots are more pointy

if you regularly had troubles with blisters between the toes (I did) then I would suggest doing something radical like wearing fivefingers which is the only total solution for me. If this is a new problems that I would agree with the others that your new trail runners are too narrow in the toe. Either swap them out now, or live with them and work at preventing blistering using some combination of toe socks or taping.

–mark

Yes, narrow toed shoes can do it, but I've more often had trouble with socks that are too tight. They hold your toes together, won't let them splay out like they're supposed to. I've experienced this both hiking and playing basketball.

You mentioned new socks, so that's my guess as to the problem.

Eventually the areas that blister will be tougher up after they heal, so I wouldnt think you would give up on any footwear/sock just because you got a few blisters.

By constantly playing musical footwear as some do in the elusive pursuit of perfection, perhaps feet never get the chance to adapt, always being bombarded in a different way, resulting in blisters in different places?

Just a thought.

Taping etc will help prevent, but doesnt do anything to develop resistance to it.

I am a believer in THIN light socks, the thinnest you can find, coupled with light breathable footwear.

I think the tight weave and no pile of thin socks allow them to slide around a bit inside shoes better than a coarser weave/pile does.

It does sound like you may need more toe room though.

Injinji.

I was just about to recommend toe socks as well.
They seem to help a lot of people will blister issues.

I had a similar experience once. The problem was one of my toe nails was a bit long and the sharp corner was digging into the next toe. I trimmed the edge of that toenail and the problem went away.