weird sensations

Every couple of months, doesn't have a certain time of day, can wake me up at night or start while watching a movie. The ears and forehead get a feeling of pins and needles, and heat sensation, but are not hot to the touch. Within a couple of minutes, my whole body starts itching, starting at the scalp. Then, raised lumps, similar to hives, but no color appear. The itching lasts about 15-20 minutes, then goes away, and so do the lumps. Weird. What could be causing this. Doesn't matter if I have eaten anything or not, whether I am inside or outside, hot or cold, or what the season is. Nothing changes as far as detergent, fabric softener, deodorant, skin lotions, etc. It is real embarrasing - has happened at church before. Please help diagnose! Lolamariee

[Dr_Aparna]

Hi,
Different people can tolerate different amounts of itching, and anyone's threshold of tolerance can be changed due to stress, emotions, and other factors. In general, itching is more severe if the skin is warm, and if there are few distractions. This is why people tend to notice itching more at night.
The reason for the sensation of itching is not well understood. While itching is the most noticeable symptom in many skin diseases, but it doesn't necessary mean that a person who feels itchy has a disease.
Stress and emotional upset can make itching worse, no matter what the underlying cause. If emotional problems are the primary reason for the itch, the condition is known as psychogenic itching.
Itching that occurs all over the body may indicate a medical condition such as diabetes mellitus, liver disease, kidney failure, jaundice, thyroid disorders (and rarely, cancer). Some people may develop an itch without a rash when they take certain drugs (such as aspirin, codeine, cocaine).
On the other hand, itching all over the body can be caused by something as simple as bathing too often, which removes the skins natural oils and may make the skin too dry and scaly.
The treatment is to corect the underlying cause.You can apply calamine lotion to soothe the skin when the sensation begins.
ref:http://www.myonlinewellness.com/topic/topic100587035