OTC. The treatment would be the same as most other allergies. Avoidance, if possible is best. Otherwise, otc claritin, (loratadine) zyrtec or allegra.
Prevention. In addition to treatment- consider prevention. Seal all cracks in cabinets where food is kept. Keep food in airtight containers & clean/ clear food particles off of / out of sinks, counters, floors etc frequently.
Allergy Shots. Are available along with avoidance.