Nippur, at present Nuffar, about one hundred miles (one hundred and sixty kilometers) southeast of Baghdad, Iraq, is occupied from around 2500 BCE.

Tablets found at Nippur describe the collection of poppy juice in the morning and its use in production of opium.

The Yanghai Tombs, a vast ancient cemetery (fifty-four thousand square miles) situated in the Turpan district of the Xinjiang Uyghur Autonomous Region of the People's Republic of China, have revealed the twenty-seven hundred-year-old grave of a shaman.

He is thought to have belonged to the Gushi culture recorded in the area centuries later in the Hanshu, Chapter 96B.

Near the head and foot of the shaman was a large leather basket and wooden bowl filled with seven hundred and eighty-nine gram of cannabis, superbly preserved by climatic and burial conditions.

An international team demonstrated that this material contained tetrahydrocannabinol, the psychoactive component of cannabis.

The cannabis was presumably employed by this culture as a medicinal or psychoactive agent, or an aid to divination.

This is the oldest documentation of cannabis as a pharmacologically active agent.

The cache of cannabis is about twenty-seven hundred years old and was clearly "cultivated for psychoactive purposes," rather than as fiber for clothing or as food, says a research paper in the Journal of Experimental Botany.

The seven hundred and eighty-nine grams of dried cannabis was buried alongside a light-haired, blue-eyed Caucasian man, likely a shaman of the Gushi culture, near Turpan in northwestern China.

The extremely dry conditions and alkaline soil acted as preservatives, allowing a team of scientists to carefully analyze the stash, which still looked green though it had lost its distinctive odor.

This shaman was Caucasoid, and was well over six feet tall.

He may belong to, or was related to the Yuezhi people or Tocharians known to have lived in the region.

Greek physician Hippocrates makes extensive use of medicinal herbs, including opium.

He dismisses the magical attributes of opium but acknowledges its usefulness as a narcotic and styptic in treating internal diseases, diseases of women and epidemics.

His compilation On Airs, Waters and Places is the first medical climatology.

Six of the eight volumes of the encyclopedia on medicine known as De Medicina describe various diseases and discuss therapy using diet, drugs, and manipulation.

Authored by Aulus Cornelius Celsus, a Roman of patrician lineage who flourishes from 10 to 37, the remaining two books deal with surgical topics, including operations for bladder stone, goiter, and hernia, as well as describing tonsillectomy and the removal of eye cataracts.

Celsus also recommends the use of splints and starch-stiffened bandages to treat fractures.

Nothing is known about the life of Celsus.

Even his praenomen is uncertain; he has been called both Aurelius and Aulus, with the latter being more plausible.

Some incidental expressions in his De Medicina suggest that he lived under the reigns of Augustus and Tiberius; which is confirmed by his reference to the eminent physician Themison of Laodicea as being recently in his old age.

It is not known with any certainty where he lived.

He has been identified as the possible dedicator of a gravestone in Rome, but it has also been supposed that he lived in Narbonese Gaul, because he refers to a species of vine (marcum) which, according to Pliny, is native to that region.

It is doubtful whether he practiced medicine himself, and although Celsus seems to describe and recommend his own medical observations sanctioned by experience, Quintilian says that his volumes included all sorts of literary matters, and even agriculture and military tactics.

De Materia Medica is the premiere historical source of information about the medicines used by the Greeks, Romans, and other cultures of antiquity.

Complied between 50 and 70 CE by the physician Pedanius Dioscorides, a native of Anazarbus, Cilicia, Asia Minor, he has written a five-volume book in his native Greek, known in English by its Latin title De Materia Medica ("Regarding Medical Materials").

The oldest surviving text on drugs and their use, the work also records the Dacian and Thracian names for some plants, which otherwise would have been lost.

Dioscorides describes drugs of plant, animal, and mineral origin and give information on drug dosage, administration, and specific uses.

Gaius Plinius Secundus, called Pliny the Elder, writes the monumental Historia naturalis, the earliest truly encyclopedic work, published in 77 as a series of anthologies concerned with such scientific and technical topics as anthropology, botany, cosmography, metallurgy, psychology, pharmacology, and zoology.

Galen of Bergama authors several hundred works (eighty of which are extant) on medicine and healing and, through experiments upon animals, founds the science of physiology.

A Greek philosopher and physician from Asia Minor who serves the emperor Marcus Aurelius, strongly influenced by Aristotle and Hippocrates’ beliefs in vital essences, Galen, though possessing practical knowledge of the circulatory system, postulates the transport of blood through vessels to the skin, where it becomes flesh.

Maintaining that knowledge of human anatomy is fundamental for a physician, he obtains anatomical facts from the dissection of animals such as pigs, dogs, and goats.

Prevented by law and custom from working with human bodies, Galen’s work, although notable, incorporates many errors when applied to human anatomy.

He nevertheless identifies numerous muscles for the first time and demonstrates the importance of the spinal cord, recording the resulting paralysis when the cord was cut at different levels.

The first to consider the pulse a diagnostic aid, he also explains the function of many nerves, discovers the sympathetic nervous system, and details almost all the structures of the brain visible to the naked eye.

His physiological theories include concepts of blood formation, digestion, and nerve function (but his insistence that tiny pores exist in the heart through which blood passes from the right to the left ventricle is an error that will be accepted throughout Europe for more than a thousand years).

Galen is an enthusiastic advocate of the virtues of opium; his books become the supreme authority on the subject for hundreds of years.

Galen had gone to Rome in 162 and had made his mark as a practicing physician.

His impatience has brought him into conflict with other doctors and he feels menaced by them.

His demonstrations here had antagonized the less able and original physicians in the city.

They plotted against him and he, fearing he might be driven away or poisoned, had left the city.

Emperor Gaozong of Tang commissions the pharmacology publication of an official materia medica in 657, documenting the use of eight hundred and thirty-three different substances for medicinal purposes.

The Persian physician Agha Bakr Muhammad ibn Zakariya al-Razi makes use of opium in anesthesia and recommends its use for the treatment of melancholy in Man la Yahduruhu Al-Tabib, a home medical manual directed toward ordinary citizens for self-treatment if a doctor is not available.

Agha Bakr Muhammad (845-930), who was born near Tehran, maintains a laboratory and school in Baghdad, and is a student and critic of Galen.

Abu al-Qasim al-Zahwari, a renowned ophthalmologic surgeon, relies on opium and mandrake as surgical anesthetics and writes a treatise, al-Tasrif, that will influence medical thought well into the sixteenth century.