Before Prohibition
Images from the preprohibition era. When many psychotropic substances were legally available in America and Europe. Notes on early psychoactive substance use in America.
For some products, such as coca wine, the formulations varied considerably across manufacturers.
Other products also showed variations (e.g. alcohol content for paregoric ranged between 18% and 46%), but USP standardization later ensured consistent formulations among chemists and commercial manufacturers.
Because opium is a natural product, early formulations using opium would have a variable opiate content, depending on growing and refining conditions (generally, opium contained 6 to 12% morphine).
Later opium formulations were more consistent as chemical assays ensured more consistent opiate content.
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