Scientific understanding of herpes zoster and postherpetic neuralgia

Author: Jie Baojuan, South District, Guang'anmen Hospital, China Academy of Chinese Medical Sciences

Reviewer: Jiang Lei, deputy chief physician, Beijing Tiantan Hospital, Capital Medical University

The herpes zoster virus is caused by the reactivation of the varicella-zoster virus that lurks in the body, and only affects humans. The herpes zoster virus is not contagious in its latent state. It will only revive when the immune system is weakened, causing the appearance of unique painful skin herpes. Generally, herpes zoster infection only occurs once in a lifetime. Immunodeficiency patients (such as leukemia, cancer, etc.) may have two herpes zoster attacks in the same skin segment, and very few people may have multiple relapses.

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The early symptoms of shingles include burning pain, stinging or itching before the rash appears, usually only on one side of the body. After a few days or weeks, a rash will appear, with erythema first appearing on the affected area, and soon papules ranging in size from millet to soybeans will appear, distributed in clusters without fusion, and then quickly turn into blisters, with skin lesions arranged in bands. It can occur on the face, neck, chest, abdomen and limbs. Because it often occurs on the waist, it is commonly known as "waist dragon" and "snake coil sore" among the people. Traditional Chinese medicine generally divides it into three types, namely liver meridian stagnation and heat type, dampness and toxicity type, and qi stagnation and blood stasis type. The following is an introduction to the symptoms and treatment methods of traditional Chinese medicine classification of shingles.

1. Liver meridian stagnation and heat type

1. Symptoms: Initial onset of blisters, red rash, herpes like millet, densely distributed in a belt-like shape. Treatment is mainly to clear the liver and purge fire, detoxify and remove dampness.

2. Medication plan: Longdan Xiegan Pills + acyclovir tablets + topical medication.

2. Dampness and toxicity accumulation type

1. Symptoms: The rash starts with erythema, which quickly turns into blisters, which cluster into patches, ulcerate and ooze pus, and cause fever and pain. The treatment is mainly to clear away heat and dampness, detoxify and relieve pain.

2. Medication plan: Chushi Weiling Decoction + acyclovir tablets + topical medication.

3. Qi stagnation and blood stasis type

1. Symptoms: Necrotic rash, hemorrhage or blood scab, purple macules and pigmentation after disappearance, residual nerve pain, sometimes stabbing pain. The treatment is mainly to promote qi and blood circulation, unblock the meridians and relieve pain.

2. Medication plan: Xuefu Zhuyu Granules + Acyclovir Tablets + topical medication.

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Precautions for herpes zoster

1. Keep warm and avoid wearing clothes that expose too much skin. Especially in cold weather and windy seasons, you should reduce the time you spend outside and rest at home.

2. Increase the intake of warm water appropriately to maintain body temperature, avoid drinking cold water, cold drinks, and tea. You can drink black chicken soup appropriately to dispel the cold.

3. Avoid rubbing or scratching the affected area to prevent the blisters from rupturing and leading to secondary bacterial infection.

4. Shingles is a viral infection. Avoid spicy food, alcohol, coffee, seafood, bamboo shoots, beef, mutton, leeks, carp, river shrimp and other irritating foods. Go to the hospital in time for antiviral and nerve nutrition treatment to avoid post-herpetic neuralgia.

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Knowledge Extension

Postherpetic neuralgia refers to pain that lasts for 1 month or more after the healing of herpes zoster lesions. The pain is diverse and can be burning, stabbing, cutting, or tearing. It is often accompanied by anxiety, depression, inattention, fatigue, anorexia, and weight loss.

The only way to prevent postherpetic neuralgia with clear evidence is to prevent the onset of shingles. A live attenuated shingles vaccine became available in 2006. The vaccine was initially approved only for immunocompromised people over 60 years of age, but is now also approved for people over 50 years of age. A randomized clinical trial in the elderly found that the vaccine reduced the incidence of shingles by 51% and the incidence of postherpetic neuralgia by 66%. Comparing people over 70 years of age with those aged 60 to 69 years, the vaccine reduced the incidence of shingles in people over 70 years of age to a lesser extent (38%), but had a similar protective effect against postherpetic neuralgia (67%). Therefore, it is wise to get the shingles vaccine as early as possible.

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