19459
Complementary studies confirmed that high - dose PHB can convert to its prodrug primidone , which has not been reported previously .
 Chemical: PHB; Chemical: primidone
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: PHB; Chemical: primidone