Carcinoid Syndrome is one possibility other than allergy.
It generally happens after stress, ingestion of spicy, hot foods, but could happen
regardless.
Check it out and see if symptoms fit.
Head and neck are typically involved in the flushing.
frootbar C.N.
I have had an allergic reaction shortly after eating and I know people who cannot eat certain foods like any meats what so ever or they breakout, sweat and swell. I would consider loggin all the times this happens and try to determine what is causing it. It would be a food allergy and as simple as cutting it out of your diet. Also, if you can predict when it will happend and could see a doctor at that time, I believe they can do a blood test and determine the cause with the test results.