the body treats the insect saliva as a toxin.
whilst on medication, we have reduced out immune responce.....
some of us do react alot more than we used to.
yes it is normal for quite a few of us to react badly to insect bites.
also deseases carried by insects are easier for us to catch.
things like ross river virus carried by mosquitos is usually caught by us.
(yes i have caught it)