Alka-Seltzer is a remedy for headache and indigestion sold over the counter.
Made by the U.S.-based Miles Laboratories, Alka-Seltzer is a combination of aspirin (acetylsalicylic acid) and baking powder (citric acid and sodium bicarbonate), designed to treat pain and simultaneously neutralize excess stomach acid (the "Alka" being derived from the word "alkali"). It is provided in the form of large effervescent tablets which are to be dissolved (two at a time for the usual adult dosage) into a glass of water; the resulting mixture, which is carbonated by the effects of the bicarbonate's reaction with the water.
The product has been extensively advertised since the beginning of the mass media era in the U.S. It was formerly marketed as something of a cure-all; at one time its ads even suggested taking it for "the blahs". Subsequent regulation has taken into consideration that aspirin is a relatively powerful drug which is not tolerated by everyone and should not generally be taken at all by children or adolescents due to its linkage to Reye's syndrome; the product is no longer marketed in this fashion.
The product has suffered a decline in popularity in recent decades; there are apparently several factors involved in this. One is the increasing medical awareness of the U.S. general public, most of whom now realize that it is not advisable to take a multi-symptom treatment product unless one has all of the symptoms that it treats (i.e., in Alka-Seltzer's case, a headache simultaneous with stomach upset.) Another is a general trend away in the U.S. from aspirin-based products to those based on other pain relievers, notably acetaminophen and ibuprofen. A third would be the product's taste, rather off-putting to some; in recent decades flavored versions have been available as a concession to that fact. At one time the product was available in both long glass tubes and foil packets; the latter is the primary way the product is provided today, with two tablets in each packet.
As the sale of the original product has declined, Miles has put the famous brand onto new products, some of which now neither are effervescent nor contain aspirin. This is because the billions of dollars building the brand through advertsing are still yielding benefits; many Americans still remember catch phrases from its ads such as "I can't believe I ate the whole thing," and "Mama mia, that was some spicy meatball." Also, millions also remember the "Speedy" character, an American advertising icon, who was either a little boy or an elf (opinions vary) whose body was primarily one Alka-Seltzer tablet while he wore another as a hat; he proclaimed Alka-Seltzer's virtues in his high, squeaky voiced to all who would listen. It seems likely that the products bearing the Alka-Seltzer brand will be available well into the future, even if the original product is not at some point.