Aim: To estimate the incidence ofpostherpetic neuralgia after being infected by herpes zoster virus.

Place and duration of study: This study was conducted in Sharif Medical & Dental College, Lahore from August 2019 to August 2020.

Methodology: A number of 126 patients was included in this research who had history of herpes zoster. Demographic information, medical diagnosis, treatment and symptoms were included in the data collected. Patients with unclear diagnosis regarding herpes zoster were not included in this study. From patient’s history, we comprehended the number of patients who developed postherpetic neuralgia after herpes zoster. Severity of pain was judged by the medications prescribed to the patients. Risk factors like age, gender, co-morbidity and localization were also analyzed. We used multivariate logistic regression to analyze potential risk factors. Risk factors were analyzed in order to determine the frequency of postherpetic neuralgia in herpes zoster patients extensively. This gave us a better idea about postherpetic neuralgia occurrence.

Results: Percentage of patients developing postherpetic neuralgia after one month of herpes zoster was 12.7% for age group 50-60. For age group 75-85, this percentage increased up to 26.8%. Neuralgia with severe pain persisted from 9 to 12 months. Mostly patients suffered mild to moderate pain up till 8 months. Patients with ophthalmic localization had 7.6% more chance of developing postherpetic neuralgia than the patients with no localization, after one month of herpes zoster. So, did the patients with co-morbidity.

Conclusion: As the results show, postherpetic neuralgia in herpes zoster patients is a frequently occurring condition. The incidence of postherpetic neuralgia increases with age. As the age increases, so does the chance of postherpetic neuralgia in herpes zoster patients. Ophthalmic localization and co-morbidity, i.e. diabetes mellitus and rheumatoid arthritis, are also related to high prevalence of postherpetic neuralgia. Female population also tend to get more postherpetic neuralgia than male population does.

Keywords: Postherpetic Neuralgia, Herpes Zoster, Incidence, Risk Factors.