U.S. regulators now say it's cool to use a nicotine replacement product while smoking, so as not to discourage people trying to quit.

After reviewing the literature, the Food and Drug Administration said concomitant use of cigarettes and nicotine-containing products "does not raise significant safety concerns." Since 1996, the regulator has allowed sale of nicotine replacement products, such as the nicotine patch, without a prescription. However, government and industry instructed consumers to quit smoking while on "the patch" and to stop after 12 weeks.

The FDA said today it plans to remove both restrictions, which unnecessarily discourages people trying to quit, some critics said. While many ignore the instructions on such products, some people tend to stop using them after relapsing and smoking a cigarette. And allowing people to use the products for longer than 12 weeks might increase chances of success, some say.

Nicotine patches and gum first came to market in 1984 and 1992, with lozenges and min-lozenges approved in 2002 to 2009.

The therapy administers nicotine to the body by means other than smoking or chewing tobacco, with transdermal and oral administration to prevent drug cravings as the user also breaks the entire family of tobacco-related habits-such as walking to the corner store to buy cigarettes or taking a smoke break at work.

The replacement reduces the incidence of smoking 1.5 to two times as compared to smokers who do not use the products. However, the products are not without their critics.

Researchers in a study from the Harvard School of Public Health and the University of Massachusetts in Boston published a report early last year in the Harvard Gazette and the online journal "Tobacco Control," asserting the therapy to be ineffective.

"Nicotine replacement therapies, specifically nicotine patches and nicotine gum, did not improve smokers' chances of long-term cessation," wrote study co-author Gregory Connolly, director of the Center for Global Tobacco Control at Harvard's school of public health. "What this study shows is the need for the [FDA], which oversees regulation of both medications to help smokers quit and tobacco products, to approve only medications that have been proven to be effective in helping smokers quit in the long term and to lower nicotine in order to reduce the addictiveness of cigarettes."

Other researchers say the therapy might be effective within the context of behavioral support and monitoring by a health care provider or counselor.