I get bitten by mosquitos all the time and they come up huge and extremely itchy, I believe some people react to them more than others as alot of people I know get bitten and they are just a pin ***** which doesn't really bother them, however mine can keep me awake at night with the iching and can get really red and swollen.
The best thing to do is not to get bitten, get some insect repellent, try not to wear perfumes, eat garlic or take capsules, some people say skin so soft works but it doesn't keep them away from me,insect spray is the best. If you do get bit vinegar works wonders.. put it directly on the bite with cotton wool or put the affected area ( if possible) in ice cold water thes two things help relive the itch. Hope this helps!!