I was in denial for awhile. All my favorite foods! But finally decided to try cutting it out for a week.
I then tried a glass of milk and didn’t notice anything. The second day, I started having abdominal pain and itchy bumps after half a glass. The third day I had another half glass and within half an hour experienced abdominal pain and itchy bumps again. The pain intensified over the next hour. I became extremely pale, was sweating profusely and nearly blacked out. After forceful vomiting and diarrhea I started to recover in the next 45 minutes or so.
Other symptoms that showed up after this reaction was: dizziness, low mood, feeling spaced out and sluggish, slight feeling of incontinence, gas, whiteheads, raspy voice, mouth sores, bleeding anus, metallic taste, and sinus pain.
One caveat was that we weren’t entirely dairy free. I didn’t remove butter from our diet, for instance, which might explain the delayed reaction, as the body was still somewhat adapted to having dairy all the time. Partly I wasn’t as strict or careful as I truly didn’t expect to have much worse reactions than say some gastrointestinal intolerance. The possibility of an actual food allergy was not on my radar. In hindsight this was extremely dangerous. Now, after being truly dairy free, reaction to a single accidental ingestion is swift and severe. Unless it is a minuscule amount, as in unintended cross contamination, pain starts within half an hour.
I was actually already intimately familiar with that full blown reaction pattern on the third day. I suffered through it many times in my life, sometimes fearing that I might not pull through and die when I black out. If I had a choice I never wanted to experience it again but there was nothing I could do as it always seemed random without a clear culprit. Within the next year I found a few other foods that cause a similar reaction and since avoiding them have finally been free of these episodes for the last few of years.
My partner got smelly watery bowel movements with milk and when he had a second glass within a day would get abdominal pain. Our first guess was lactose intolerance, but turns out he has the exact same pattern with lactose free milk. So our current guess is that he probably has a milk protein intolerance. Along with gastrointestinal symptoms he gets headaches. Other suspected symptoms are bruxism (nighttime teeth grinding), dizziness, sneezing, and spacing out.