Boston officials approved some of the toughest anti-tobacco rules in the nation Thursday, extinguishing cigar bars and hookah bars and ending the sales of tobacco in pharmacies and on college campuses.

The Boston Public Health Commission, however, decided to give the bars 10 years before they would have to close, doubling the original proposed grace period for the establishments. Even then, the bars could seek an extension for another 10 years.

Boston is the largest city, by far, to move to outlaw smoking bars, which have been exempt from the city's four-year-old workplace smoking ban.

"As we all know, smoking is the number one cause of preventable cancer deaths in the U.S.," said Dr. Paula Johnson, chairwoman of the commission.

"It's very important that we really think about what are the steps we can take to make our city as healthy as it can possibly be," she said.

The commission gave preliminary approval in September to the rules, which will take effect on campuses and pharmacies in 60 days.

The panel also voted to expand the workplace smoking restrictions to include and hotels, inns and bed and breakfasts, as well as areas such as loading docks.

Under the new regulations, operators of a smoking bar whose permit is current or whose application was pending before the commission by Nov. 1 will be able to operate for a period of not more than 10 years. After 10 years, they can petition for one 10-year extension.

Roger Swartz, who heads the commission's community initiatives bureau, said the panel lengthened the grace period for the bars because of hard economic times.

"We wanted to give them a bit more time to get used to the idea that they'll have to close," Swartz said.

The meeting was attended by a handful of cigar bar patrons, including Stephen Helfer, 61, Cambridge, who held a sign urging the panel not to close the bars.

"This is just an incremental step toward total prohibition," he said.

Right now, there are no state bans on smoking bars; 52 communities nationwide have bans that include private clubs and cigar bars, according to Americans for Nonsmokers Rights. Fort Wayne, Ind., is among the largest communities with such bans, and smaller cities in Massachusetts also have them.

The ban on tobacco sales in pharmacies is not as unique in big cities; a similar ban went into effect in San Francisco in October, despite a pending court challenge.