Postherpetic Neuralgia (PHN)

Postherpetic neuralgia (PHN) is a complication of shingles, which is caused by the varicella-zoster virus - the same virus that causes chickenpox. PHN is characterized by persistent pain in the area where the shingles rash occurred.

Causes and Risk Factors

PHN occurs when the varicella-zoster virus reactivates and travels down nerve fibers to the skin, causing inflammation and damage to the nerves. The risk of developing PHN increases with age, with people over 60 years old being more likely to experience PHN. Other risk factors include:

• Severity of the shingles rash
• Delay in treating shingles
• Weakened immune system

Symptoms

The symptoms of PHN can vary from person to person, but common symptoms include:

• Persistent burning or aching pain in the affected area
• Sharp, stabbing pains
• Itching or numbness in the affected area
• Sensitivity to light touch or temperature changes

Diagnosis

PHN is typically diagnosed based on a person's medical history and physical examination. The diagnosis is often made when:

• A person has had shingles
• Pain persists for more than 3 months after the shingles rash has healed
• Other possible causes of pain have been ruled out

Treatment and Management

Treatment for PHN usually involves a combination of medications, including:

• Anticonvulsants, such as gabapentin or pregabalin, to help reduce nerve pain
• Antidepressants, such as amitriptyline or nortriptyline, to help reduce pain and improve mood
• Pain relievers, such as acetaminophen or ibuprofen, to help manage pain
• Topical creams or patches, such as lidocaine or capsaicin, to help numb the skin and reduce pain

In addition to medication, other treatments that may be used to manage PHN include:

• Physical therapy to improve mobility and reduce stiffness
• Occupational therapy to improve daily functioning
• Cognitive-behavioral therapy to help manage stress and anxiety related to chronic pain

Prevention

The best way to prevent PHN is to prevent shingles from occurring in the first place. The Centers for Disease Control and Prevention (CDC) recommends that adults 50 years old and older receive the shingles vaccine, which can help reduce the risk of developing shingles and PHN.