The decline of laudanum usage in the early 20th century coincided with the rise of regulated pharmaceuticals, particularly following the Harrison Narcotics Tax Act of 1914. This legislation aimed to control the distribution of narcotics, leading to a significant reduction in laudanum's availability in the U.S. and Europe. The shift marked a turning point in public health policy and the regulation of substances, influencing the modern pharmaceutical landscape.

The decline of laudanum with the rise of regulated pharmaceuticals in 1910 marked a transition in literature from romanticized tonics to stigmatized substances. Poets like T.S. Eliot and H.D. reflected on the complexities of addiction and societal change in their works.