I frequently have nausea, headaches, and alternating cold chills and hot flashes after eating. I ve been trying to limit dairy in case it s lactose intolerance, but the symptoms persist. I actually feel better if I don t eat! If not lactose intolerance, I m wondering if it could be a medication or supplement that I take either causing these issues on its own or interacting with another med. Also, I take acetaminophen every day. What is the definition of too much acetaminophen? If a medication is to blame, however, it doesn t explain why I feel worse after eating. I m a 52-year-old female, approximately 25 pounds overweight. I had a hysterectomy a little over a year ago, and I had a gastric bypass approximately 10 years ago.