Advil is a brand name for ibuprofen, which is a nonsteroidal anti-inflammatory drug (NSAID) used to relieve pain, fever, and inflammation. According to the sources provided, ibuprofen was discovered in 1961 by Dr. Stewart Adams, a British pharmacologist, and it was first marketed as a prescription drug in the United Kingdom in 1969 [3].

Advil was first introduced in the United States in 1984 by Whitehall-Robins Healthcare, which is now part of Pfizer [2]. It was initially available only by prescription, but in 1985, the US Food and Drug Administration (FDA) approved Advil for over-the-counter (OTC) use [1]. Since then, Advil has become a popular OTC pain reliever, and it is now available in various forms, including tablets, capsules, and liquid gels.

In summary, ibuprofen was discovered in 1961 and first marketed as a prescription drug in the United Kingdom in 1969. Advil, which is a brand name for ibuprofen, was first introduced in the United States in 1984 and approved for OTC use by the FDA in 1985.

Sources:
[1] DrugPatentWatch. Advil. https://www.drugpatentwatch.com/p/tradename/ADVIL. Accessed 18 May 2021.
[2] Advil. Our Story. https://www.advil.com/advil-story/. Accessed 18 May 2021.
[3] Wikipedia. Ibuprofen. https://en.wikipedia.org/wiki/Ibuprofen. Accessed 18 May 2021.