1557
In order to evaluate the efficacy , time - course of action and predictors of response to topical capsaicin , 39 patients with chronic post - herpetic neuralgia ( PHN ) , median duration 24 months , were treated with 0 . 025 % capsaicin cream for 8 weeks .
 Chemical: capsaicin; Disease: post - herpetic neuralgia; Disease: PHN; Chemical: capsaicin
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Disease, Chemical 
Text: {0} 
Answer:
 Chemical: capsaicin; Disease: post - herpetic neuralgia; Disease: PHN; Chemical: capsaicin