“The dose makes the poison”


Paracelsus considered himself an alchemist, however his ideas on poison led to the introduction of chemistry into medicine in the sixteenth century. Although he was not fully appreciated until his death, medicine would be a different field without his contributions.

As at the 16th century most physicians in medieval Europe had little interest in drugs and still adhered to the ancient teachings of Galen on rebalancing the body’s humours (Phlegm, Blood, Black bile & Yellow bile) in order to treat illness.

Paracelsus, by name, Philippus Aureolus Theophrastus Bombastus von Hohenheim took the name Paracelsus (meaning “beyond Celsus”, the Roman physician) to show his rejection of ancient Roman teaching after studying medicine at universities in Austria, Switzerland, and Italy.

Shortly after acquiring his degree(1510), he decided to travel far and wide, travelling through almost all the countries in Europe and eventually to Egypt before returning home to Basel, Switzerland. He travelled to learn “practical” alchemy and discover the most effective medical treatments, choosing to learn from folk healers and alchemists rather than through formal university education that relied on traditional teachings of Galen and Ibn Sina (Avicenna).

“The universities do not teach all things, so a doctor must seek out old wives, gipsies, sorcerers, wandering tribes, old robbers, and such outlaws and take lessons from them. A doctor must be a traveller… Knowledge is experience.”


After arriving from his travels (1524), Paracelsus would rise to fame for many of his miraculous cures that had preceded him. He was subsequently appointed town physician and lecturer in medicine at the University of Basel in Switzerland, where he made all his lectures open to every resident of the town. In these lectures, he stressed the healing power of nature and denounced the use of methods of treating wounds, such as padding with moss or dried dung, that prevented natural draining. The wounds must drain, he insisted, for “if you prevent infection, Nature will heal the wound all by herself.” He also attacked many other medical malpractices of his time, including the use of worthless pills, salves, infusions, balsams, electuaries, fumigants, and drenches.

Barely 4 years after returning to Basel, he had fallen into disrepute with local doctors, apothecaries, and magistrates. He would leave in 1528 and continue to travel for the next 8 years. During this period of travelling he revised old manuscripts and wrote new treatises. With the publication of Der grossen Wundartzney (Great Surgery Book) in 1536 he restored, and even extended, the revered reputation he had earned at Basel. He became wealthy and was sought by royalty.

By 1538 he returned to Basel and by 1541 he died under mysterious circumstances in White Horse Inn, Salzburg, where he had taken up an appointment under the prince-archbishop, Duke Ernst of Bavaria.

Contributions to Medicine

  • Instead of an imbalance in bodily fluids, Paracelsus regarded disease as an intrusion into the body – in some ways anticipating germ theory.
  • In 1530 Paracelsus wrote a clinical description of syphilis, in which he maintained that the disease could be successfully treated by carefully measured doses of mercury compounds taken internally.
  • He stated that the “miners’ disease” (silicosis) resulted from inhaling metal vapours and was not a punishment for sin administered by mountain spirits.
  • Paracelsus is also given credit for the invention of laudanum, derived from powdered opium and alcohol, which became the prime relief for people in severe pain until the discovery of morphine in the 19th century
  • Paracelsus was the first to connect goitre with minerals, especially lead, in drinking water.
  • He pioneered the use of minerals and other chemicals in medicine. Mercury, lead, arsenic and antimony—poisons to most—were cures in his view. Antimony was used as a purgative and gained much popularity after it was used to cure Louis XIV.

Though we think of Paracelsus as the first medical chemist, he thought of himself as an alchemist, and his writings are rife with astrology and mysticism, even his preparations of chemicals sound like passages out of a grimoire. But he had the soul of a scientist; he preferred direct experience over the ancient authorities.

“Consider, I beseech you, this tiny grain of seed, black or brown in color, producing such wonderful greenness in its leaves, such variegated colors in its flowers, and flavors in its fruits of such infinite variety; see this repeated by Nature in all her products, and you find her so marvelous, so rich, in her mysteries that you will have enough to last you all your life in this book of Nature without referring to paper books.”


Ireoluwa Adegoke
• The Medicine Book by DK