Charles H. Phillips Chemical Company

The Charles H. Phillips Chemical Company was a pioneering American pharmaceutical firm best known for the invention and commercialization of Phillips' Milk of Magnesia. Founded in the mid-19th century by Charles Henry Phillips, the company specialized in magnesium-based compounds for digestive health. Its flagship product, magnesium hydroxide, became a global standard for treating heartburn and constipation after being patented in 1873. The company was acquired by Sterling Drug in 1923 and its brands eventually transitioned to Bayer following a series of corporate mergers and acquisitions. Today, the Phillips brand remains a leading name in the over-the-counter gastrointestinal health market.