ATC code P Antiparasitic products, insecticides and repellents is a section of the Anatomical Therapeutic Chemical Classification System, a system of alphanumeric codes developed by the WHO for the classification of drugs and other medical products.

National issues of the ATC classification may include additional codes not present in this list, which follows the WHO version.

The Anatomical Therapeutic Chemical (ATC) Classification System is used for the classification of drugs. It is controlled by the WHO Collaborating Centre for Drug Statistics Methodology (WHOCC), and was first published in 1976.

This pharmaceutical coding system divides drugs into different groups according to the organ or system on which they act and/or their therapeutic and chemical characteristics. Each bottom-level ATC code stands for a pharmaceutically used substance in a single indication (or use). This means that one drug can have more than one code: acetylsalicylic acid (aspirin), for example, has A01AD05 as a drug for local oral treatment, B01AC06 as a platelet inhibitor, and N02BA01 as an analgesic and antipyretic. On the other hand, several different brands share the same code if they have the same active substance and indications.

In this system, drugs are classified into groups at 5 different levels:

The first level of the code indicates the anatomical main group and consists of one letter. There are 14 main groups:

Kurt Schneider (7 January 1887 – 27 October 1967) was a German psychiatrist known largely for his writing on the diagnosis and understanding of schizophrenia, as well as personality disorders then known as psychopathic personalities.

Schneider was born in Crailsheim, Kingdom of Württemberg, and trained in medicine in Berlin and Tübingen. He was drafted for and completed military service in World War I and later obtained a postgraduate qualification in psychiatry. In 1931 he became director of the German Psychiatric Research Institute in Munich, which was previously founded by Emil Kraepelin.

Disgusted by the developing tide of psychiatric eugenics championed by the Nazi Party, Schneider left the institute (when?) and served as an army doctor (for who?) during World War II. After the war, anti-Nazi academics were appointed to serve in, and rebuild Germany's medical institutions and Schneider was given the post of Dean of the Medical School at Heidelberg University. Schneider kept this post until his retirement in 1955.