Many moderate to severe rosacea sufferers experience burning while they flush. The blood vessels release heat and inflammatory substances that act on sensory nociceptors (pain receptors) and this signals back to your brain........burning. These nerves can then stay activated for quite some time after the flushing is gone.
Now, one of the most frustrating things for rosacea sufferers is experiencing burning sensations chronically without flushing (invisible burning syndrome). We thought in the past that most of this was due to chronically inflammed sensory nerves. But recent evidence indicates that sympathetic nerves in the face "communicate" with sensory neurons in the face. Thus activation of sympathetic nerves during stress, heat, foods, excertion, etc. can selectively activate sympathetic nerves which release norepinephrine onto receptors on sensory neurons and trigger a burning reaction without any visible signs. More frustrating is that low grade constant sympathetic stimulation can result in days/weeks of chronic burning sensations. These are the folks that want to just jump off the largest building they can find.
I will try to get an updated article on Neuropathic Rosacea published and get it submitted to a Neurology based medical journal because they are ideally trained for this ........ but dont know it yet.
I hope at the very least, this helps explain the disorder a little better, make it known that this is "not in your head" and better educate you guys and gals so that you can better educate your physicians.