Mosquitoes, Help!!!!?

I have recently moved from England to Mexico and am getting eaten alive by mosquitoes.Some of the bites i get swell up to over 15 cm diameter and i have a rash where i have been bitten, presumably as an allergic reaction to the bite. I have tried vit B tablets, sprays and creams to prevent them from biting me but nothing seems to work. Alcohol works but only for a vey limited time and i cant be drunk all day everyday, as much as i would like to be. A mosquito net is not an option because i am very claustrophobic and couldnt sleep with this over me. Is there anything else i can try?