Clinical Efficacy and Safety of Tender Point Infiltration (TPI) for Acute and Subacute Zoster Associated Pain

The conventional therapies for HZ infection can be seen in two phases. Those in acute phase are mainly antiviral (acyclovir, famciclovir, etc.), analgesic drugs (opioids, acetaminophen or nonsteroidal anti-inflammatory agents, gabapentin, etc.), while these conventional drug therapies could yield potential side effects, and part of patients are not fully satisfied with the analgesic effect. It is considered that supplementary and alternative local therapies may have better results with less side effects and reduce medical costs to relieve pain associated with HZ infection. These options, including nerve blockade (epidural injection, paravertebral injection, sympathetic block, intercostal nerve block, intracutaneous injection), pulsed radiofrequency16, acupuncture, fire needling acupuncture, electrical nerve stimulation19, lidocaine patch, capsaicin cream, and botulinum toxin injection have been reported to give positive therapeutic effects on acute herpes zoster neuralgia (AHN), however, evidence for the efficacy of existing local therapies is limited and risks may occur due to high invasiveness of some procedures, there is insufficient evidence and expert agreement to make recommendations for these intervention strategies as first-line treatments in guidelines.