Sentence: Concentrations of guaifenesin , diphenhydramine , and chlorpheniramine detected in the heart blood were 27.4 , 8.8 , and 0.2 mg/L , respectively .
Drug combination annotation:
[{'class': 'NEG', 'spans': ['guaifenesin', 'diphenhydramine', 'chlorpheniramine'], 'is_context_needed': True}]