As consequence to the whole event, there may be excess compliment throughout the body with no antigen to fight. I guess this can also explain kicking an addictive drug such as alcohol, tobacco or heroin. They would have shakes, cramping, headaches and severe cravings. I usually had them use a little of the offending food a time or two in small quantities to reduce the reaction. It depends on the degree of symptoms.
Correction depends upon proper analysis and recommendations.
Most of the lab testing is fairly inexpensive and does not need to be repeated too much. Most of the cases of food problems in general can be cleared up by simply reducing or avoiding the offending substance for a reasonable period of time.