My neck has been itching for months it is worse when i have been in the sun and when i am hot it is only from under my chin down to my lower neck, two ?

Itching Neck: Itching is usually due to release of histamine. This may be blocked by taking an antihistamine. Topical irritants / allergens may be found in soaps, detergents, anything you apply to your skin. Are you using a sunscreen? This could trigger the reaction. Look at everything you are applying to your skin. Sometimes, a change in how you are cleaning your clothes will explain.