Several different types of herpes virus are known to infect humans and cause disease. These conditions include genital herpes, oral herpes, and herpes zoster. The latter, also called HZ but better known colloquially as "shingles," is caused by the same type of virus that produces chicken pox earlier in life; symptoms of shingles include severe nerve pain, rash and itching with lesions usually confined to the trunk. Sometimes, and more often with increasing age, pain persists after the lesions have healed, a state known as post-herpetic neuralgia, or PHN.
Skin Sensitivity
The rash that accompanies HZ sometimes gives way to depigmented areas of skin as a result of melanin depletion. These areas often become extremely sensitive to touch, resulting in allodynia, or pain from a stimulus that is normally not painful, according to StopPain.org. People with PHN-induced allodynia may experience pain or discomfort when very lightly touched, as when brushed by clothing; in some patients, a small change in temperature can elicit pain. Some who do not have allodynia, instead have severe sensory loss, while others have either both or allodynia alone.
Pain
The prevailing symptom in people with PHN is pain in the same areas that were affected by HZ itself. This pain may be steady with bursts of worsening pain or intermittent with spasms arising spontaneously and at unpredictable intervals. The spontaneous type varies in quality and can be burning, throbbing, tingling, stabbing, piercing, shooting, sharp or aching. Pain may occur in concert with intense itching in the same area or areas.
Muscle and Joint Pain
As a result of a patient's continual guarding of affected areas, PHN is often accompanied by pain in the muscles and joints of the upper extremity. Because this is strictly a secondary symptom that arises in response to the nerve pain symptoms, it abates when the nerve pain itself does.
Depression and Anxiety
Unrelenting or serious intermittent pain is as much an emotional factor as it is a neurological one, and people with PHN often become depressed, worried or otherwise distressed as a result, notes StopPain.org. Also, pain may keep sufferers from getting adequate amounts of sleep, which itself can contribute to mood disturbances and a decline in general day-to-day function. Patients should be sure to discuss any such symptoms with a physician in order to minimize their impact.
Muscle Weakness
Ordinarily, HZ affects the sensory nerves while sparing motor neurons from pathology. However, in some cases, muscle weakness or even paralysis in an affected area may occur. Fortunately, this is a rare complication.
