3297
Analyses of a blood sample revealed unusually high plasma concentrations of metoprolol ( greater than 3000 ng / ml ) and diltiazem ( 526 ng / ml ) .
 metoprolol, diltiazem
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Disease, Chemical 
Text: {0} 
Answer:
 metoprolol, diltiazem