Comparison of effectiveness of daily intake and twice weekly intake in low dose oral immunotherapy for food allergy - investigator-blinded, randomized, parallel group controlled trial -

INTERVENTION: the participants in frequent group intake the allergic food daily in low dose oral immunotherapy the participants in intermittent group intake the allergic food twice weekly in low dose oral immunotherapy CONDITION: Food allergy PRIMARY OUTCOME: Difference of amount of intake in oral food challenge after 12 +‐ 2 months from start of low dose oral immunotherapy between frequent (daily intake) group and intermittent (twice weekly intake) group. SECONDARY OUTCOME: Primary outcome which divided into subgroup of egg allergy and milk allergy. ; Difference of Egg white and ovomucoid‐sIgE or milk and casein‐sIgE after 12 +‐ 2 months from start the OIT between the frequent and the intermittent groups, which divided into the egg and the milk subgroups. ; Difference of Egg white and ovomucoid‐sIgE or milk and cazein‐sIgG4 after 12 +‐ 2 months from start the OIT between the frequent and the intermittent groups, which divided into the egg and the milk subgroups. ; Difference of increasing rate of amount of intake in oral food challenge from before the OIT to after the OIT between the frequent group and the intermittent group. ; Difference of increasing rate of ovomucoid‐sIgE in egg allergy and milk‐sIgE in milk allergy from before the OIT to after the OIT between the frequent group and the intermittent group. ; Difference of the FAQ after 12 +‐ 2 months from start of the OIT between the frequent group and the intermittent group. ; Difference of the VAS scale for degree of difficulty of intake the foods after 12 +‐ 2 months from start of the OIT between the frequent group and the intermittent group. INCLUSION CRITERIA: Children aged 6 months or older, 6 years or younger Children who were diagnosed with a positive by open oral food challenge (OFC) with boiled egg white / milk, which total dose of 1‐10 g. Excluding positive only for the symptoms around the oral cavity. There are blood test results within 3 months of OFC which performed prior to study registration. Children who can be Track one year and track confirmation OFC one year later. A person who consented to the study by a substitute person who is a parental author in writing.