Allergies are a common cause of hives since an allergic reaction can trigger the immune system response that results in trapped fluid beneath the skin.An allergic reaction can occur due to something you ingested or were exposed to through the air.hoto Credit pollen image by asb from Fotolia.com. Allergies are a common cause of hives since an allergic reaction can trigger the immune system response that results in trapped fluid beneath the skin. An allergic reaction can occur due to something you ingested or were exposed to through the air.
The median nerve, which runs through the arm and hand, can cause swelling pain and numbness if injured. Ulnar nerve injury Damage to the ulnar nerve causes swelling, pain and numbness in the forearm, hand, and ring and little fingers.
Your leg may fall asleep for different reasons, but it most often is due to nerve irritation. If you sleep on your leg a certain way or leave your legs crossed for too long, there may be sustained pressure on the nerve. This can cause the feelings of pins and needles once the pressure from the nerve is relieved.