Hello, I get the same symptoms..
Itchy under my chin,
itchy back, coughing and wheezing, usually at night. I read that they are asthma symptoms and that asthma symptoms can be caused by an allergic reaction to food, drink, pollen, dust etc, even if you don't usually suffer with asthma. I sometimes used my mums inhaler when it happened, but when I read this, tried taking and ANTIHESTHAMINE to find it MASSIVELY REDUCED THE SYMPTOMS.