4288
OBJECTIVE : To report two cases of a possible adverse interaction between clonidine and verapamil resulting in atrioventricular ( AV ) block in both patients and severe hypotension in one patient .
 Chemical: clonidine; Chemical: verapamil; Disease: atrioventricular ( AV ) block; Disease: hypotension
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: clonidine; Chemical: verapamil; Disease: atrioventricular ( AV ) block; Disease: hypotension