2600 BC – Imhotep wrote texts on ancient Egyptian medicine describing diagnosis and treatment of 200 diseases in 3rd dynasty Egypt.
2596 BC – The Huangdi Neijing (Yellow Emperor's Classic of Internal Medicine) is published, laying the framework for traditional Chinese medicine
1500 BC – Saffron used as a medicine on the Aegean island of Thera in ancient Greece
500 BC – Bian Que becomes the earliest physician known to use acupuncture and pulse diagnosis
420 BC – Hippocrates of Cos maintains that diseases have natural causes and puts forth the Hippocratic Oath, marking the birth of medicine in the west
280 BC – Herophilus studies the nervous system and distinguishes between sensory nerves and motor nerves
250 BC – Erasistratus studies the brain and distinguishes between the cerebrum and cerebellum
200 BC – the Charaka Samhita uses a rational approach to the causes and cure of disease and uses objective methods of clinical examination
50–70 – Pedanius Dioscorides writes De Materia Medica – a precursor of modern pharmacopeias that was in use for almost 1600 years
180 – Galen studies the connection between paralysis and severance of the spinal cord
220 – Zhang Zhongjing publishes Shang Han Lun (On Cold Disease Damage), the oldest medical textbook in the world
270 – Huangfu Mi writes the Zhenjiu Jiayijing (The ABC Compendium of Acupuncture), the first textbook focusing solely on acupuncture
400 – the Sushruta Samhita is published, laying the framework for Ayurvedic medicine
- Basic timeline of the progression of Medicine (wiki)