3723
Combined administration of ornithine and phenylacetate ( OP ) is proposed as a novel treatment of hyperammonemia and hepatic encephalopathy .
 Chemical: ornithine; Chemical: phenylacetate
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: ornithine; Chemical: phenylacetate