Hugo Paul Friedrich Schulz (August 6, 1853 - July 13, 1932) was a German

Germany

Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

 pharmacologist

Pharmacology

Pharmacology is the branch of medicine and biology concerned with the study of drug action. More specifically, it is the study of the interactions that occur between a living organism and chemicals that affect normal or abnormal biochemical function...

 from Wesel

Wesel

Wesel is a city in North Rhine-Westphalia, Germany. It is the capital of the Wesel district.-Division of the town:Suburbs of Wesel include Lackhausen, Obrighoven, Ginderich, Feldmark,Fusternberg, Büderich, Flüren and Blumenkamp.-History:...

, Rhenish Prussia. He studied medicine in the universities of Heidelberg and Bonn

University of Bonn

The University of Bonn is a public research university located in Bonn, Germany. Founded in its present form in 1818, as the linear successor of earlier academic institutions, the University of Bonn is today one of the leading universities in Germany. The University of Bonn offers a large number...

, where he did scientific work in the physiological

Physiology

Physiology is the science of the function of living systems. This includes how organisms, organ systems, organs, cells, and bio-molecules carry out the chemical or physical functions that exist in a living system. The highest honor awarded in physiology is the Nobel Prize in Physiology or...

 institute of Eduard Friedrich Wilhelm Pflüger

Eduard Friedrich Wilhelm Pflüger

Eduard Friedrich Wilhelm Pflüger was a German physiologist born in Hanau.He studied medicine at the Universities of Marburg and Berlin, earning his doctorate in 1853. While in Berlin he worked as an assistant to Emil du Bois-Reymond...

 (1829-1910). In 1877 he earned his doctorate, and in 1883 was appointed professor of pharmacology at the University of Greifswald.

Schulz is known for his research of a phenomenon

Phenomenon

A phenomenon , plural phenomena, is any observable occurrence. Phenomena are often, but not always, understood as 'appearances' or 'experiences'...

 known as hormesis

Hormesis

Hormesis is the term for generally favorable biological responses to low exposures to toxins and other stressors. A pollutant or toxin showing hormesis thus has the opposite effect in small doses as in large doses...

, which shows that toxins can have the opposite effect in small doses than in large doses. He proved this in his experiments with chemical compounds on yeast

Yeast

Yeasts are eukaryotic micro-organisms classified in the kingdom Fungi, with 1,500 species currently described estimated to be only 1% of all fungal species. Most reproduce asexually by mitosis, and many do so by an asymmetric division process called budding...

 cells. From his research came the Arndt-Schulz rule

Arndt-Schulz rule

Arndt–Schulz rule or Schulz' law is a claimed law concerning the effects of pharmaca or poisons in various concentrations. It states that:...

, a law concerning dosages in toxicology

Toxicology

Toxicology is a branch of biology, chemistry, and medicine concerned with the study of the adverse effects of chemicals on living organisms...

; named along with Dr. Rudolf Arndt

Rudolf Arndt

Rudolf Arndt was a German psychiatrist from Bialken, district of Marienwerder.Arndt studied in Greifswald and Halle, preferably under Felix von Niemeyer , Heinrich Adolf von Bardeleben , and Heinrich Philipp August Damerow , and was conferred doctor of medicine on 20 February 1860...

(1835-1900).

Schultz published several works in the field of pharmacology; his 1898 book Pharmakotherapie being the best known.