Hi, welcome to the forum, recurrent attacks of allergy suggests Hereditary angioedema (HAE), which is a rare genetic disorder resulting from an inherited deficiency or dysfunction of the C1 inhibitor. This may be associated with laryngeal swelling leading to respiratory obstruction. Hence, it is important to rule out this condition.
There are many tests (various types of Immunoassays and Total IgE levels) are available which indicates the severity of allergy but we cannot predict his betterment.
At this time you need to restrict the foods and factors to which he is allergic to. You will eventually come to know about his improvements.
I suggest you to consult dermatologist for further management. Take care and regards
I would recommend that you find a board certified and preferably a board fellow allergist to take your child to. Many of the symptoms you describe can be allergy related. See if the allergist would recommend allergy testing at that point.