Allergic Reaction to bites all over my body! Unsure as to what is biting me though!

Patient: Hi, i have bites all over my body. i am allergic to bee and wasp stings and also some bites. stings send me into anaphylactic shock and bites make me swell and blister, also making me feel rather sick if i have a few. i dont know what i am getting bitten by but they are making me very sick and generally unwell, is there anything i can do to stop my body swelling and blistering?