I get a stuffy nose from milk unless the milk is cultured, cooked, or turned into cheese. My guess is somehow the culturing for yogurt or fermenting for cheese-making breaks down whatever part of the protein I'm allergic to. My Allergist suggested also the possibility of a hormone reaction (vaso-vegal) and that boiling milk for 5 minutes removes this component...I'm not convinced, however, because I'm ok with small amounts of uncooked (but still pasteurized) milk if I don't do it too often.
My Brother has a major caseine allergy and the only cheese he is ok eating is Provalone (salt-cured in addition to the fermentation for cheese-making). He gets violently ill from milk or other forms of dairy.
Also, the whey proteins are broken down from culturing or cooking, so you might consider this possibility too...
Allergy tests are not always the most accurate, either - there can be false negatives or false positives with every single test method out there (skin prick/scratch, blood RAST/CAP-RAST IgE, blood ELISA IgG/IgA/IgM, blood ALCAT, skin patch, kinesiology, EDS, etc. - even the double-blind oral challenge can yield false negatives)...
Chronic Lyme, Bart., Gluten & Sulfite Sensitivity, Many Food/Inhalant/Medication/Chemical Allergies & Intolerances, Asthma, Gut dysmotility & non-specific inflammation, UCTD, Osteoporosis, etc.; G-Tube
Meds: Ceftin, Singulair, Claritin, Domperidone, Milk Thistle, homeopathy, probiotics, etc.