The first thing you should do if you have skin allergies is to make an appointment with an allergist. He or she will test you to diagnose exactly what you are allergic to. Your doctor may do a skin prick test, applying small amounts of diluted allergens to scratches on the skin of your arm or back and checking for reactions after 15 to 20 minutes, or a patch test, taping allergens to your skin and checking for reactions after 24 hours and again after 48. If necessary, your doctor will prescribe medications to treat your skin allergies.
Once you know what you are allergic to, the best way to deal with your skin allergies is to avoid the allergens. These allergens may range from food and drug ingredients to pollen, dust or other things in the air, to perfumes and cosmetics and materials such as latex. The less contact you have with whatever it is you're allergic to, the less likely it will be for your skin to have any reactions.
If you react to an allergen, treatment will depend on what kind of reaction you have. If you have eczema (a scaly, red, itchy rash), you can try cold compresses, calcineurin inhibitor cream, topical steroids and antihistamines. If you have hives (itchy, red, raised areas) and/or angioedema (a swelling of the deeper layers of the skin - usually the eyelids, tongue, lips, hands and feet), use cool compresses, take cool showers and wear light or loose clothing. Your doctor may also prescribe antihistamines or steroids.
Finally, if you have contact dermatitis (a painful red blistered reaction), scrub the affected skin with soap and water; use cool compresses, calamine lotion, milk soaks, oatmeal baths, antihistamines and cortisone medications for relief. It may take up to four weeks for contact dermatitis to go away completely.