Since then it has become a popular adult medication as well, in part because it doesn't cause stomach upset. It doesn't reduce swelling like aspirin, and large overdoses can cause liver damage. Acetaminophen began as a children's medication, and, is still the preferred pain reliever for children due to the connection between Reye's syndrome and aspirin in children with influenza or chicken pox. Acetaminophen is found in Tylenol, and in Bristol-Myers Squibb's Excedrin, which contains both aspirin and acetaminophen.

As for the small drug company that first sold acetaminophen, McNeil Laboratories grew quite large, thanks to the success of its Tylenol, and eventually became a subsidiary of Johnson & Johnson.

Ibuprofen

ibuprofen

In the early 1960s scientists figured out that certain organic acids, like aspirin, were good at reducing inflammation. The Boots Company, a British drug maker, synthesized over 600 new organic acids looking for anti-inflammatory drugs. A scientist named Stuart Adams made one called ibuprofen that was twice as potent as aspirin as an anti-inflammatory. It was first sold in the United Kingdom as an arthritis treatment and later in the United States as the prescription drug Motrin.

Ibuprofen products.

Since 1984 it has been available over-the-counter under names like Advil, Motrin IB, and Nuprin. Ibuprofen can cause stomach upset (though not as often as aspirin), but on the positive side, regular use has been linked to a reduced risk of Alzheimer's disease, though the evidence is not yet conclusive. It is thought that ibuprofen works by inhibiting the body's ability to make prostaglandins, much like aspirin does.

Naproxen Sodium and Ketoprofen

Naproxen sodium and ketoprofen are powerful pain relievers that became available over-the-counter in the mid-1990s. Naproxen sodium is sold by Bayer under the name Aleve and ketoprofen is sold by American Home Products under the name Orudis KT. Both appear to work by inhibiting prostaglandins, like aspirin does. But also like aspirin, they can cause stomach upset and other gastrointestinal problems. Take a look at the molecular structures of these drugs and you'll see they are chemically similar to ibuprofen.

naproxen sodium

Naproxen sodium and ketoprofen   products.

ketoprofen

COX-2 Inhibitors

Severe arthritis patients are often treated with ibuprofen, naproxen sodium, or ketoprofen. While these drugs usually don't cause stomach problems at the doses found in medicines sold over-the-counter, at the higher doses used in prescription drugs gastrointestinal bleeding and ulcers may occur.

These drugs, and aspirin, work by inhibiting cyclooxygenases. One cyclooxygenase, called COX-2, helps make the prostaglandins that help us feel pain. But another, COX-1, helps protect the inside of your stomach. Recently scientists have been investigating COX-2-inhibiting drugs that leave COX-1 alone. These are the so-called superaspirins, and they tend to be more powerful and cause less stomach and intestinal trouble than other analgesics.

celecoxib

rofecoxib

Both celecoxib and rofecoxib were designed specifically to be COX-2 inhibitors. The scientists who created them designed their molecular structures using what was known about how different molecules interact with the body. In this sense, they are designing drugs much in the way that Felix Hoffmann and Arthur Eichengrün did over one hundred years ago.

Now that you've learned all about the different analgesics out there, it might be a good time for an activity in which you get to decide which one is best for a given patient. This activity is called Compare the Painkillers.

Next: Salsa Analgesica

Mann, Charles C., and Plummer, Mark L. The Atlantic Monthly, 1988, 262(4), 39.

McGrath, Kimberly, ed. World of Invention, 2nd ed. Detroit: Gale Research, 1999.

Additional reading

Underwood, Anne. "Life After Vioxx," Newsweek, January 31, 2005, p. 40.

Image credit

Early Tylenol^® packages: Courtesy McNeil Consumer Health Care. Photo by Will Brown.