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A total of 261 adverse ocular reactions occurred in 237 patients who received isotretinoin , a commonly used drug in the treatment of severe cystic acne .
 Chemical: isotretinoin; Disease: acne
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: isotretinoin; Disease: acne