I've seen the word air hunger used with respect to me/cfs, and I'm wondering how to tell if that's what I have. It feels difficult to get enough air, as if I'm taking half a breath instead of a whole one. I don't have mucus. It feels sore and tiring if I expand my lungs all the way. I feel like if I sleep, I'll stop breathing from lack of energy, but that doesn't happen. (I'm not referring to sleep apnea.) I'm not sure whether to go to the doctor or not, because I'm sure all my tests will be normal as usual, but it's disconcerting to feel a lack of oxygen. Can ketotifen cause this? Have any of you had this before? What were your symptoms?