Allergic conditions are difficult to treat, the best is to keep away from what you are allergic to. In case you come in contact with substance you are allergic to , immediately take antihitamine tablet before the condition aggrevates.
One long term for treatment of allergy is to do desensitisation, it works, but let me warn you, it is a long drawn process, takes months to complete and the effect lasts for 3-5 years, after that the whole treatment needs to be repeated.
For good sleep, first thing is to be stress free, keep your self fit by regular physical excercise and eat a healthy diet.
Taking sleeping medicine should be the last resort.