eat some yogurt. i think i figured it out from too much rum at thanksgiving. my stomach was upset and it hurt to eat. the binge drinking disrupted my 'gut flora', the microorganism responsible for healthy intestines. other bacteria formed colonies, and my scalp started itching. i also noticed an increase in normal itching, like if nose grease gets in an eye, or the reflex to touch myself. bacteria can live in your hair i think, but usually doesn't because flora keep them in your intestines. even when you know your body is clean, your intestines may not be.

"lifestyle and environmental factors can greatly reduce the number of friendly bacteria allowing pathogenic bacteria to take hold and cause problems. Both friendly and pathogenic bacteria can and are affected by changes in the intestinal environment. Bacterial infections, stress, traveling, antibiotic treatment, alcohol, poor diet, aging and a number of other factors can and do disturb the delicate bacterial balance, often decreasing the number of beneficial bacteria while allowing an overgrowth in pathogenic bacteria."

Do not let your doctor confuse this with your brain playing tricks on you or welcome an antipsychotic prescription. Doctors like practicing medicine. Psychiatrists like practicing medicine. I don't appreciate some of the medical psychological language used when its just an upset stomach. Last thing, the tingle on the scalp could occur for a while after your stomach is healthy, then fade away until its not noticable.