Eat, drink and be merry, for we have antacids.

As Americans indulge in holiday feasts and festivities and cope with the accompanying stresses, their consumption of heartburn remedies hits its peak.

During the 2004 holiday season, for example, Americans purchased more than $78 million worth of antacids -- more than during any other four-week period last year according to market research firm, ACNielsen.

Although Tums is introducing a new 12-count "Take Out" pack that's suitable for stocking-stuffing, it's not likely that Tums, Pepto-Bismol or Rolaids ever will become must-have gifts.

But that doesn't make them any less popular.

"People are tending to eat heavier meals in the winter months," said Jean Barry, director of brand management for GlaxoSmithKline Consumer Products, which manufactures Tums. "Also, certainly during the holidays, they're eating at a lot of parties, maybe eating foods they don't eat normally, and they're tending to eat more."

The seasonal bump in sales is one of many tummy-tranquilizing messages being stressed by Glaxo's marketing team as Ms. Barry and her colleagues in the North American headquarters of Glaxo's consumer division, which is based in Moon, mark the 75th anniversary of Tums this year.

Despite red hot competition among heart burn remedies in recent years, Tums has remained one of the top five antacid tablets in the United States during each of the last four years, according to Information Resources, Inc., a Chicago firm that tracks sales at supermarkets, drug stores and mass merchandisers, excluding Wal-Mart.

Set against newer competitors such as Prilosec OTC that draw on the latest science for fighting heartburn, the old antacid tablets are offering smoother and chewier formulations, as well as new flavors. Tums, for example, just launched its new Cocoa and Creme flavor, while Rolaids now comes in cherry and vanilla.

Antacid tablet makers also stress their lower price and the speed with which they can neutralize stomach acids.

"They're less expensive, and if they work for you, they will work faster," said Randy Juhl, a vice chancellor at the University of Pittsburgh and former dean of the pharmacy school.

"If I were advising a consumer, and the indigestion that I got was successfully and satisfactorily treated by chewing on a couple antacid tablets, that's the way I'd go," added Mr. Juhl, who directed a Food and Drug Administration panel during the 1990s that oversaw the switch of four prescription heartburn medications to over-the-counter products, including Glaxo's Tagamet.

For GlaxoSmithKline, Tums ranks No. 2 among the more than 30 over-the-counter brands in the company's roster of consumer products in North America. Led in net sales by its smoking cessation product Nicorette, the Moon-based consumer products division generated $1.6 billion in revenue during 2004.

While Tums has been a steady generator of revenue for Glaxo-SmithKline, to the tune of about $200 million annually, sales were hurt initially following the introduction of Prilosec OTC in late 2003, said Ms. Barry. Tums bounced back by stressing the immediate relief it can provide, she said, saying some customers jumped to Prilosec OTC not realizing that it is a "regimen" product that people take for 14 days.

Marketed by Procter & Gamble, the over-the-counter version of Prilosec had an impact not just on Tums but on the entire over-the-counter antacid category, helping sales grow from about $800 million during 2003 to nearly $1 billion this year, according to ACNielsen, which measures sales at food, drug and mass merchandiser stores, excluding Wal-Mart. Because it must be taken for weeks, Prilosec OTC does not experience a holiday bump in sales, said a Procter & Gamble spokeswoman, but the company's Pepto-Bismol does flow more freely during December.

Likewise, sales of Alka-Seltzer increase during the holidays, said Tricia McKernan, spokeswoman for Bayer Consumer Care. Bayer announced yesterday that, like Glaxo, it is celebrating its past. Alka-Seltzer, which is in the process of remaking its classic "I Can't Believe I Ate the Whole Thing" ad campaign, will mark its 75th anniversary in 2006.

Tums was introduced commercially in 1930 by the Lewis Howe Co. in St. Louis, where it is still manufactured. Since 1986, marketing for Tums has stressed not just its gastrointestinal benefits, but also its status as a calcium supplement. Pregnant women often are encouraged to take Tums for its calcium benefits, a message that Glaxo promotes by providing obstetricians with free samples of the product, said Ms. Barry, the marketing executive. The calcium message has helped Tums protect its business from newer competitors such as Pepcid and Zantac, said Mr. Juhl, the Pitt official. As women live longer, their need for calcium supplements to prevent osteoporosis only will increase, he said.

The over-the-counter antacid category stands to be shaken up again next year, said Mr. Juhl, when Prilosec OTC is scheduled to loose market exclusivity, which will allow other companies to offer similar products. That should lower prices.

Lori H. Lukus, spokeswoman for GlaxoSmithKline, said the company isn't worried about the coming competition.

In other words, Glaxo officials aren't popping antacids.