A stop sign is posted near CVS/pharmacy on February 5, 2014 in Miami, Florida. - 

In a first for a major drugstore chain, CVS will stop selling cigarettes and other tobacco beginning in October. That will wipe out an estimated $2 billion a year in sales, but CVS believes it can more than make up the difference by expanding services to promote better health.

Troy Brennan, Chief Medical Officer for CVS Caremark, joined us to talk about the company's decision.

"As a health care company, you just can't be selling the number one public health problem," Brennan says.

Click play on the audio player above to hear the whole interview.

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