<s>[INST] I have been hearing/having what I can only explain as a sizzling sound in my head for a few weeks that comes and goes. I get dizzy and light-headed when I have it. Sometimes it seems to come from the back of my neck also. Any idea what this could be or what could be causing it? [/INST] Hi and thanks for asking Chat Doctor, You should know that these symptoms lead to wide differential diagnosis.First before having an appointment with your GP you should exclude deny Chat Doctor. These situations could be the cause of your malaise.Meanwhile, you should have your blood pressure monitored BCS hypertension and hypotension are part of the differential diagnosis. Maybe with this you will need your GP consultation too for the right management and a blood cell count is needed to exclude anemia.These is some few tips so that you could clarify yourself these symptoms if not you should have an appointment with your doctor. Hope you will get better soon. Feel free to ask for any other information. </s>