Postherpetic neuralgia in the elderly can be treated with medications, botulinum toxin injections and nerve blocks. 1.Drug treatment (1) Gabapentin: such as gabapentin and pregabalin, which can improve pain symptoms by reducing glutamate release, raising the excitation threshold of injurious receptors and increasing the level of inhibitory amino acids. Side effects include rash, drowsiness, dizziness, etc. It is contraindicated in patients with acute pancreatitis and pregnant women. (2) Tricyclic antidepressants: such as amitriptyline, relieve neuropathic pain by inhibiting the presynaptic reuptake of biogenic amine serotonin and norepinephrine. Side effects include dizziness and headache, palpitations, constipation, etc. It is contraindicated in patients with heart disease, epilepsy, glaucoma and pregnant women. 2. Botulinum toxin injection: Botulinum toxin is injected into the subcutaneous area of the pain area to reduce pain by inhibiting the release of sensory inflammatory mediators and peripheral neurotransmitters. Side effects include erythema, tightness, infection, etc. It is prohibited for patients with myasthenia gravis and multiple muscle sclerosis. 3. Nerve block therapy: Depending on the area of the lesion, the innervated ganglion or nerve root is identified, and an anesthetic or steroid is injected to help alleviate the pain, and the effect can last from a few weeks to a few months. Patients are advised to visit a dermatologist or pain medicine department and be guided by a doctor.