Effect of repeated paravertebral injections with local anesthetics and steroids on prevention of post-herpetic neuralgia

INTERVENTION: Patients will receive paravertebral block using 25 mg bupivacaine 0.5% plus 8 mg dexamethasone in a total volume of 10 ml three times one week apart under fluoroscopy CONDITION: chest wall herpetic eruption post‐herpetic neuralgia PRIMARY OUTCOME: Lower the incidence of post herpetic neuralgia which will be evaluated by visual analogue scale SECONDARY OUTCOME: Analgesic consumption was assessed by patient self‐report Pain severity was assessed using Visual Analogue Scale (VAS), (10 cm unmarked line in which 0 = no pain and 10 cm=worst pain imaginable INCLUSION CRITERIA: INCLUSION CRITERIA: patients over 50 who had chest wall herpetic eruption of less than one week, with moderate and severe pain and received appropriate antiviral therapy.