If you have the urge to scratch your forearm, or you feel like it's tingling, you might have Brachioradial pruritus. Sun exposure and spinal issues might be at fault. Treatments range from ice packs to physical therapy to medications and possibly surgery.
Brachioradial pruritus is a nerve disorder that causes itching, stinging, or tingling sensations in this area of the outer forearm. Brachioradial pruritus usually affects both arms, but it can occur in only one arm. In rare cases, the urge to scratch spreads to other parts of the body, including the shoulders, neck, and lower legs. This condition is not contagious.
For further information please go to https://my.clevelandclinic.org/health/diseases/21181-brachioradial-pruritus