What is Liebermeister's rule?

Liebermeister's rule concerns the increment ratio between an adult individual's cardiac frequency and temperature when in fever. Each Celsius grade of body temperature increment corresponds to an 8 beats per minute increase in cardiac frequency, although the exact number of this rule varies significantly across different sources. An exception to this rule by creating a relative bradycardia is known as Faget sign common in some diseases, especially yellow fever, tularaemia and salmonella typhi.

It is named for Carl von Liebermeister.