Acetanilide is a synthetic compound that was first used for its fever reduction and painkilling properties in the late Nineteenth Century. For many years it was utilized as an alternative to aspirin to treat various ailments, but large-scale medical use dissipated when the toxic side effects of consuming acetanilide became apparent.

In the body, acetanilide is partially converted into a mixture of acetaminophen and aniline. Acetaminophen provides painkilling characteristics, but aniline is toxic and interferes with the hemoglobin of the blood. When its dangerous properties were realized, chemists sought an alternative and soon developed a synthetic version of acetaminophen. This manufactured substance quickly replaced acetanilide in pharmacies because it is not as prone to generate blood disorders, and it continues to be widely used today.

Yet, acetanilide has not completely disappeared from the marketplace since other applications for the white crystalline substance have been found. The compound most frequently acts as an intermediate product used in items such as photographic materials, rubber, and dyes. However, acetanilide may also be used in herbicides, nail polishes, and in the production of varnishes.