It is very similar to how it feels when a limb “falls asleep” only instead of the sensation going away after you stop laying on that limb in an odd position, it just stays around without any apparent reason and without easing up. This can be caused by some sort of nerve interruption (such as a lesion) in the central nervous system (CNS).
How to Treat Paraesthesia
The pins and needles were one thing but the itching was unbearable! I usually had it on my scalp and I wanted to scratch my skin off! Nothing helped, not antihistamines (like Benadryl), not a cold shower, not even scratching, I just had to deal with it and worse than the physical sensation itself was the emotional frustration of having nothing to do about it: I was helpless.