Bromo-Seltzer is an antacid

Antacid

An antacid is a substance which neutralizes stomach acidity.-Mechanism of action:Antacids perform a neutralization reaction, increasing the pH to reduce acidity in the stomach. When gastric hydrochloric acid reaches the nerves in the gastrointestinal mucosa, they signal pain to the central nervous...

 used to relieve pain occurring together with heartburn

Heartburn

Heartburn, also known as pyrosis or acid indigestion is a burning sensation in the chest, just behind the breastbone or in the epigastrium...

, upset stomach, or acid indigestion. Originally produced by inventor Isaac E. Emerson's Emerson Drug Company of Baltimore, Maryland, Bromo-Seltzer is sold in the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 in the form of effervescent granules which must be mixed with water before ingestion

Ingestion

Ingestion is the consumption of a substance by an organism. In animals, it normally is accomplished by taking in the substance through the mouth into the gastrointestinal tract, such as through eating or drinking...

.

In the days of classic radio, it was known for its slogan which was repeated rhythmically in imitation of a railroad steam engine: "BRO-mo-Selt-zer, BRO-mo-Selt-zer, ..." There is also a clock tower in Baltimore

Baltimore

Baltimore is the largest independent city in the United States and the largest city and cultural center of the US state of Maryland. The city is located in central Maryland along the tidal portion of the Patapsco River, an arm of the Chesapeake Bay. Baltimore is sometimes referred to as Baltimore...

, Maryland

Maryland

Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...

, known as the Bromo-Seltzer Tower

Emerson Bromo-Seltzer Tower

The Emerson Bromo-Seltzer Tower was erected in 1911 at the corner of Eutaw and Lombard Streets in Baltimore, Maryland. It was designed by Joseph Evans Sperry and was constructed by Bromo-Seltzer inventor "Captain" Isaac E. Emerson. It was the tallest building in Baltimore from 1911 until 1923...

, which has the name written on the face of the clock in lieu of the hours.