A restricted food diet is never a good idea as you keep taking things out of the diet and will find it difficult to re-introduce. Food allergies
worsening ezcema are not very common while some observational studies report eggs, milk, shrimp to worsen eczema
in children. Other studies have suggested an association with wheat.
Therefore it is always best to get a skin test (when you are NOT on antihistamines) as specific IgE blood test
for eczema may sometimes give false positive results if the total IgE is high (>1000), confusing the picture.
If you definitely have any food allergies, it is worth mentioning to your allergist before the test is done.
Eczema can flare due to house dust mite or animal allergens so it is important these are also checked at the same time.