What did Montag kick and why is this significant?

He kicked a medicine bottle. Montag hates Mildred's desire to be in a chemically induced state of vacant daze. Mildren overdoses on the same pills. 

"The object he had sent tumbling with his foot now glinted under the edge of his own bed. The small crystal bottle of sleeping-tablets which earlier today had been filled with thirty capsules and which now lay uncapped and empty in the light of the tiny flare."