My Husband has a lot of food allergies too, and he has found a combination of Zyrtec, Singulair, and swallowing a mixture of Budesonide nebulizer suspension with xylitol helpful (his reactions are localized to wherever the food touches - mouth, esophagus, stomach, etc.).
Also, low thyroid is thought to cause an increase in allergies - have you had your thyroid checked (TSH, Free T3, Free T4, thyroid antibodies) recently?
You might consider asking your Allergist about a condition called Eosinophilic Esophagitis - this condition can cause people to develop lots of allergies (and is what my Husband has). The test for this condition is looking at biopsies of the esophagus that are obtained through an upper endoscopy procedure.
I hope this helps - take care,
Chronic Lyme Disease, Gluten & Sulfite Sensitivity, Many Food/Inhalant/Medication/Chemical Allergies & Intolerances, Asthma, Gut issues (dysmotility, non-specific inflammation), UCTD ("Secondary Lupus-Like Syndrome"), Osteoporosis, Pancytopenia, chronic malabsorption/malnutrition, etc.; G-Tube; Currently TPN-dependent.
Meds: Zofran, Pulmicort, Heparin (to flush PICC line), Claritin, Colloidal Silver (used topically), IV Milk Thistle, probiotics.