My friend is on oxygen and I was trying to do some research for him. He was operated on about seven years ago and since then he has developed allergy to plastic and newsprint. Now, his problem is the tubes that they use to give him oxygen. He is put on oxygen when his blood levels go below 90. When he is made to put on the oxygen mask and the nasal tubes it is ok for about 15-20 minutes and then he feels constricted in the throat as if it is closing in and he is even worse than when he did not have the oxygen. Has anyone heard anything like this? He was given the latex allergy test and we are still awaiting results. Does anyone know what to do in a situation such as this? I think that he must be given a medic alert bracelet He also suffers from really bad asthma and I was wondering if there has been anyone who has been on oxygen had any issues of this sort.