Brachioradial pruritus (BP) is a condition where the person experiences intense itching, burning and/or stinging to one or both arms. The itching often occurs between the shoulder and the elbow on the sides of the arms but can also extend up to the shoulders.
Scratching can make the itching feel worse, rather than bringing relief. Using ice packs is one treatment that may calm the itch.
Why brachioradial pruritus occurs is unclear. There are two basic mechanisms that are thought to be the cause of this uncontrollable itch.
The first is the solar hypothesis. It is thought that people who have had chronic sun exposure develop an allergic type of histamine response in their skin.
This theory receives some support from the fact that people usually report more left-sided symptom over right-sided. This could be explained by the sun shining more on the left arm while driving.
In South Africa, where drivers sit on the right side of the car, the incidence of BP more frequently affects the right arm. Symptoms also often are worse in the summer and improve in the fall.
The second hypothesis is that BP may be caused by a neuropathy (problem with the nerves), specifically some type of irritation or compression of the cervical nerves in the neck. Treatments for cervical arthritis have shown to improve those with the condition.
This type of itching is called a neuropathic itch. Impulses are sent due to hypersensitivity of the nerve fibers. Sometimes people feel both pain and itching, as well as some type of sensory disruption such as altered sensation in the area.
A 1987 study even suggested that BP may be caused by a combination of the two stating that, “brachioradial pruritus is a photoneurological disorder caused by sun-induced damage to nerve endings that results in pruritus and altered sensation in susceptible individuals.”2
Another dermatology blog suggests that exposure to wind may also contribute.3
However, there are critics to both main theories.
The solar critics point out that people’s faces get just as much sun as the arms, so why doesn’t one’s face develop this problem?