The Merck Manuals

The Merck Manuals are medical references published by the American pharmaceutical company Merck & Co. (known as MSD outside the United States), that cover a wide range of medical topics, including disorders, tests, diagnoses, and drugs. The manuals have been published since 1899, when Merck & Co. was still a subsidiary of the German company Merck.

These manuals were originally developed in book form, but have been updated and converted to digital formats, including websites and mobile apps. Digital versions also include audio, 3D models, and animations.

The first Merck Manual, Merck's Manual of the Materia Medica (1899), was a small reference book that became widely used: by the 1980s it had become the world's best-selling medical text. Since then, several manuals have been produced, and are regularly updated. The titles include:

The Manuals for human health were converted to a web format in 2015 and are hosted on MerckManuals.com in the US and Canada, and MSDManuals.com throughout the rest of the world. The sites includes two versions tailored for consumers and health care professionals. The Manuals are available online in 10 languages. The Manuals for animal health were converted to a web format in 2002 and are hosted on MerckVetManual.com.

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