Patients with very sensitive milk allergy can react to a very small quantity of milk, or milk protein, including minor contamination, or inhalation of milk powder. Milk contamination of a product is possible if the same manufacturing equipment is used for various products. There is also a carryover effect when one product is used in the manufacture of another. You should be aware when ordering sliced products from a place that uses the same tool to slice all foods.
Hypoallergenic milk formulas have been used as a milk replacement for children with milk hypersensitivity. However, hypoallergenic milk formulas are not non-allergenic, and many children react to the formula.
Soy products are often used to replace the use of cow’s milk, with people assuming that the soy milk will be free of cow’s milk. THIS IS NOT TRUE! “Vegetarian” cheese may contain cow’s milk protein. This term means that the rennet used in its manufacture is of vegetable origin.
Labels that indicate the presence of Milk Protein:
Artificial butter flavor, butter, butter fat, buttermilk solids, carmel color, caramel flavoring, casein, caseinate, cheese, cream curds, emulsifier, "de-lactosed' whey, demineralized whey, dried milk, dry milk solids, fully cream milk powder, high protein flavor, lactalbumin, lactalbumin phosphate, lactose, milk, milk derivate, milk protein, milk solids, natural flavoring, pasterized milk, protein, rennet casein, skim milk powder, solids, sour cream, sour milk solids, whey, whey powder, whey protein concentrate, and yogurt.
WARNING!:!: Casein (a milk protein) may be found in soy milk, and also is found in baby formulas- Although the label says they are milk free. (This is because they are not "milk protein free")
When finding a milk replacemenet, be aware if you are allergic to gluten! A lot of rice milks has gluten in it, some are labeled, some are hidden. I found a brand of milk at Whole Foods, "365 Organic Rice Milk" and I seem to do OK with it.
If you can not find a rice milk that you are not allergic to, then try this milk! I have been using it, and as far as I know I am not allergic to it! Good Luck! 
