Taken from The Hagley Museum and Library Website:
Patent medicine promoters pioneered many advertising and sales techniques. Patent medicine advertising often touted exotic ingredients, even if their actual effects came from more practical elements. The producers of many of these medicines used a primitive version of branding to distinguish themselves from their many competitors.
Within the English-speaking world, patent medicines are as old as journalism. The marketing of patent medicine formulas fueled the circulation of early newspapers. Newspaper and magazine advertising helped spread the word of these nostrums to the country's most remote corners.
Advertising for patent medicines was not limited to newspapers and almanacs. Printed broadsides were major sources of commercial information. Early broadsides dealt with epidemics, providing suggestions to prevent the spread of diseases. In the early 18th century broadside advertisements by druggists and apothecaries began to surface, usually in the form of product lists offered for sale. Later, broadsides with lengthier texts, describing the value of proprietary medicines and frequently joined by testimonials, accompanied these lists.Trade cards were very popular in the Victorian era. They typically featured a very colorful, eye-catching picture with advertising slogans on the front side, and full advertising text (and sometimes testimonials) on the back. Varying from funny to risqué, trade cards immediately became popular collectors’ items.
Here are some billhead examples. Interestingly, when the public was finally informed of the "quack" nature of these patent medicines, the companies that made them started selling sundries and soap goods.