Advil is a brand name for the drug Ibuprofen, which is a nonsteroidal anti-inflammatory drug (NSAID) used to treat pain and inflammation. According to Drug Patent Watch [1], the first patent for Ibuprofen was filed in the United Kingdom in 1961 by Boots Pure Drug Company. However, it was not until 1974 that Ibuprofen was approved for use in the United States by the Food and Drug Administration (FDA).

Advil was first introduced in the United States in 1984 by Whitehall-Robins Healthcare [3]. The brand was initially marketed as a prescription drug, but it became available over-the-counter in 1985. Since then, Advil has become a popular pain reliever and fever reducer.

In a study published in the Journal of Clinical Pharmacology [2], it was noted that Ibuprofen was first synthesized in 1961 by Dr. Stewart Adams, a pharmacologist at Boots Pure Drug Company. Adams was searching for a drug that could relieve pain and inflammation without the side effects associated with other NSAIDs. He discovered that Ibuprofen was effective in reducing pain and inflammation and had fewer side effects than other NSAIDs.

In conclusion, Ibuprofen, the active ingredient in Advil, was first synthesized in 1961 by Dr. Stewart Adams. However, it was not until 1974 that Ibuprofen was approved for use in the United States by the FDA. Advil was first introduced in the United States in 1984 by Whitehall-Robins Healthcare and became available over-the-counter in 1985. [1][2][3]

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/ADVIL
[2] https://pubmed.ncbi.nlm.nih.gov/22098129/
[3] https://www.advil.com/advil-story/