Something like seventeen years ago, I discovered this as well and gratefully enjoyed my cookie. Not ten minutes later, I was spewing fluid from every orifice I have. I developed hives, too. Also, I didn't realize until someone told me, but apparently I had an extreme pallor.

I've never had an allergic reaction to a cookie before, nor an allergic reaction that severe to any food item. I hadn't consumed anything else suspect that day. It was bad enough that, once I had a sufficient break in my extensive leakage, I went to the hotel lobby where the hotel manager happened to be; he took one look at me and immediately went to call an ambulance without even asking me.

Once I was in the ambulance, even the paramedics commented on the volume and violence of my still ongoing reaction.

I was hospitalized overnight and it went away on its own over several hours. I was at a hotel for a week of on-site training for a new job and somehow the employer heard about it - I got major credit for showing up to the first day of training the next morning despite the circumstances.

Nothing else went wrong health wise during that trip but I haven't stayed at that chain since.

edit: Corrected a word.