2690
H1 - and H2 - histamine antagonists or placebo were given before dosing with d - tubocurarine in a randomized double - blind fashion to four groups : group 1 - - placebo ; group 2 - - cimetidine , 4 mg / kg , plus placebo ; group 3 - - chlorpheniramine , 0 . 1 mg / kg , plus placebo ; and group 4 - - cimetidine plus chlorpheniramine .
 Chemical: histamine; Chemical: d - tubocurarine; Chemical: cimetidine; Chemical: chlorpheniramine; Chemical: cimetidine; Chemical: chlorpheniramine
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: histamine; Chemical: d - tubocurarine; Chemical: cimetidine; Chemical: chlorpheniramine; Chemical: cimetidine; Chemical: chlorpheniramine