This summer I had tested a new mosquito itch remedy. It's a shelf stable solution and I think that it
neutralizes whatever the mosquito injects by oxidation. The recipe is this:
18ml of clean water (not tap water)
2ml of 100% DMSO
5 drops of a 25% sodium chlorite solution (NaClO2)
I put this into a small 20ml dropper bottle and carry it with me.
I have tested it all summer and it is very effective. I apply this once I have discovered a new red itching spot somewhere. The red spot and the itch will go away within an hour after rubbing a few drops of this liquid onto the spot.
My wife does not like it because it causes her to have a new slightly red spot (not as red as the mosquito spot) where the liquid was applied. The red mosquito spot goes also away in her case but it seems to irritate her skin a little bit. That irritation lasts a few hours.
I have however used it with great success throughout the summer.
A variant of this recipe is to dissolve a tiny bit of xantan gum in hot water before adding DMSO and NaClO2. This makes a gel and it is easier to apply than the pure watery solution. The DMSO prevents this gel from getting moldy. Store this in a small glass jar (not acryl plastic) as DMSO dissolves PVC and acryl plastics.