I have had my throat close up from some medications but the one that went beyond that was when a reaction to Penicillin caused me to have a sense of doom and my brain felt like it was twisting inside my head. It's hard to describe really and a doctor recently told me "that's not an allergy" even though at the time the doctor seeing me told me that it was and that the next time I take Penicillin I could die. I think I'll choose never to take it again.