My reactions typically happen days later after I have ingested gluten. I will get all of a sudden very bloated, with the feeling of trapped gas and constipation. My fingers start to tingle and that brings an increased heart rate and anxiety. I have occasionally felt very faint and felt like I couldn't catch my breath almost mimicking an asthma attack. I also will have excessive burping and acid reflux. The initial attack is very scary, feeling like I can't breathe and the pins and needles sensations. After those symptoms subside, I usually am still bloated, constipated, and have acid reflux/chest pain for the next few days. I have yet to figure out how to help my symptoms or stop the anxiety/asthma attacks when this happens. Definitely a freaky feeling!