I used to get a similar reaction when i was a child, i even got sent home from school once they got so bad.

You can get antihistamines from your local chemist. they work for me.

Go to the doctors and be careful I moved from Canberra to the Northern Rivers and then came down with viral menangitas which is carried by  mozzies not  very nice so go see the doctor as I said

My Chloe has Skeeter syndrome which just means she's allergic to mozzies lol

My doc has said if she gets bitten to spray her with ventonlin ASAP because it stops the swelling, weird but true! I find a dab of teatree oil takes the itch out for her aswell.

Prevention is the best thing with mozzie allergies so make sure you do everything possible to stop her being bitten :)

my daughter is the same way her's get bigger then a half dolar at times I took her in last summer for it and they told me that mosquito bites are allergic reations and some people just react worse and to give her Benadryl which didn't work for her, but then he said Zartec which works great you could also try after bite it comes in a liquid stick that you can just rub on it takes the itch away 

stingoes.... i swear by it. my baby has the same reaction to mozzies aswell. so does my MIL I also 20 mins before bed spray her room and keep it closed.

we also keep the house to make sure there is nothing they can breed in like puddles of water.

 I dont know what others think but maybe a trip to the dr just to make sure its not to bad, or maybe just to the clinic nurse. Otherwise Pinetarsal is ment to be good on itchy skin, and im pretty sure my clinic nurse said it was fine for babys, i was itchy during this pregnancey and it helped a lot, Very strong smell of pine tho. Just go to the chemast and they should beable to help aswel :)