CVS has stopped selling tobacco – as it moves to strengthen its focus on public health.
The pharmacy chain, which is the second-largest in the US after Walgreens, has implemented the change nearly a month sooner than planned.
And it has also tweaked its corporate name from CVS Caremark to CVS Health to reflect the shift – although the signs on its roughly 7,700 stores will remain the same.
But customers will notice the difference at the tills, where the familiar site of shelves stacked with cigarettes has been replaced with nicotine gum and anti-smoking signage.
CVS said it expects to lose about $2 billion (£1.2 billion) in revenue annually after pulling tobacco from its stores, but executives believe they can counter that loss at least in part through growth the company may get from health care.
However, the potential revenue loss hasn't spooked investors so far. CVS shares have climbed about 22 per cent since the announcement. Shares rose 83 cents to $80.56 (£48.95) in afternoon trading.
The company, which is ranked 12th in the 2014 Fortune 500, announced in February that it would phase out tobacco sales by 1 October, because it could no longer sell cigarettes in a setting where health care is offered.
Pharmacies in the US have placed more emphasis on customer health in recent years, in part to serve the millions of uninsured people who are expected to gain coverage under the federal health care overhaul.
However, rivals Walgreens and Rite Aid have no plans to stop selling tobacco.
CVS chief executive Larry Merlo said in a statement: "By eliminating cigarettes and tobacco products from sale in our stores, we can make a difference in the health of all Americans.
"As CVS Health, we are tobacco-free, reinventing pharmacy and taking our place among leaders in the health care community."
Additional reporting by Associated Press