Avicenna’s Systematic Reviews

That great medieval polymath and philosopher Ibn Sina (d. 1037), or Avicenna as he is known in the West, might in fact be regarded as father (or inventor) of medical systematic reviews [1], nowadays considered as the highest level of evidence for efficacy of medical treatments, might be new for some, at least for me, before I’d read an interesting 2007 dissertation of, well, a dentist, Jinan Rashid (in German).

Ibn Sina was born around 980 CE in the village Afshana in the vicinity of Bukhara in Transoxiana. He was the son of a respected scholar of the Ismaili sect from Balkh who took care of his overarching education. Although Shi’ite, his father served as high-ranked official in the Sunnite Samanid Emirate. Considered a child prodigy, Ibn Sina had studied the Holy Qur’an and contemporary classical literature before the age of ten years and had started studies in medicine when 16. He was permitted to use Sultan Nuh ibn Mansur’s vast library in Bukhara for completing his medical studies after he had been counseled, albeit to no avail, the seriously ill Sultan at age 17.

Avicenna’s most important work in the medical realm is of course his five volumes of Al-Qanun fi t-tibb which had been completed around 1020 and which had already been translated into Latin in the 2nd half of the 12th century by Gerhard of Cremona (d. 1187). It was also one of the first books which had been printed in original Arabic after Johannes Gutenberg’s (d. 1468) ground-breaking invention of movable print typing. Avicenna’s Canon of Medicine, as it is known in the West, became quickly the standard medical textbook in all European universities until the 16th and 17th centuries [2].

Avicenna’s Qanun mainly collated and elegantly summarized medical knowledge and conceptions of pre-Islamic medicine, i.e. that of Greek Antiquity and late Antiquity. There is hardly any Islamic medicine in it with one notable exception, namely the, as the Prophet Muhammad demanded, frequent use of the miswak, a toothpick made of twigs of the Arabian scrub Salvadora persica, for tooth cleaning. In fact, Avicenna’s views were based on Galen’s (d. ca. 200) humorism about excess or deficiency of the four bodily fluids black and yellow bile, phlegm, and blood,  rather than what has been called the Prophet’s medicine based on traditions according to ahadith.

The Qanun served physicians as leading medical encyclopedia for centuries and, beginning with the 18th century, historic and scientific literature about the Qanun grew exponentially at a rapid pace. The Canon had long been translated into Hebrew, Urdu, and Persian; and in modern times into Russian and Japanese. But it is quite amazing that only parts of the huge work are yet available in English translations. Rashid’s dissertation provides, for the first time, a German translation of certain dentistry-related parts of the Qanun.

That the Qanun contains elaborated paragraphs about dentistry (in particular in volume III, which is dealing with special anatomy and physiology as well as pathology and therapy of diseases of any organ from head to toe, here sections 7 and 8; the latter about oral mucosal and gum diseases was not dealt with in Rashid’s dissertation) might be amazing at first sight; but given Avicenna’s highly systematic and comprehensive approach that should merely be logic and self-evident for the famous polymath. What Avicenna describes, in particular measures for preventing tooth decay, tooth erosion, gum disease, discoloration, or bad breath, sounds both reasonably familiar but sometimes pretty weird, for instance his advice to use a mixture of sugar and honey for polishing teeth before applying, for example essence of roses or other essential oils.

Anyway, did the world-renowned professor and princeps medicorum perhaps practice dentistry himself?

Well, probably not. Rashid’s most revealing part of her interesting dissertation deals with comparative translations of six older than Avicenna’s works [3] in which dental topics had been dealt with, in particular four Arabic authors of the 8th till 10th centuries which have not been quoted by Avicenna [4]. While 75-80% of the texts corresponded with the older works, in many cases literally, Avicenna’s versions seem to be more concise and far more systematical, elegant. For instance, while Hunain provides a similar version of polishing teeth with sugar and honey, he emphasizes mechanical properties; while Avicenna mentions, in addition, different indications according to humorism.

Rashid concludes that Avicenna most likely did not publish his own original work when writing about dental problems. His intention was rather to comprehend contemporary knowledge and put it in order according to philosophical aspects. In a way a systematic review of what was available in the literature which he knew well. The Qanun had been devised as encyclopedia and reference guide, well, without references [5].


[1] Avicenna discussed in his major medical work, the Qanun fi t-tibb which is the topic of this post, how to effectively test new medicines based on seven conditions for “The recognition of the strengths of medicines through experimentation”:

  1. The drug must be free from any extraneous accidental quality.
  2. It must be used on a simple, not a composite, disease.
  3. The drug must be tested with two contrary types of diseases, because sometimes a drug cures one disease by its essential qualities and another by its accidental ones.
  4. The quality of the drug must correspond to the strength of the disease. For example, there are some drugs whose heat is less than the coldness of certain diseases, so that they would have no effect on them.
  5. The time of action must be observed, so that essence and accident are not confused.
  6. The effect of the drug must be seen to occur constantly or in many cases, for if this did not happen, it was an accidental effect.
  7. The experimentation must be done with the human body, for testing a drug on a lion or a horse might not prove anything about its effect on man. (Emphasis added.)

Thus, several fundamental criteria for clinical trials were met one thousand years before evidence based medicine (EBM) emerged. I find it particularly intriguing that Avicenna considered animal experimentation as no evidence, something which is still not clear to many scholars in clinical medicine.

[2] Yes, I like mentioning Avicenna when entertaining my students about what is considered a scientific impact nowadays. The Qanun truly made an impact!

[3] Hunain ibn Ishaq (9th century), two books by Abu Bakr ar-Razi (turn of 9th to 10th century), al Magusi (about 975), Abu Sahl al-Masihi (d. 1010) who is considered Ibn Sina’s direct teacher, and one pre-Islamic author, Paul of Aegina (7th century).

[4] Avicenna refers, in the Qanun, only once to Galen; in general, in medieval times authors were not mentioned unless they were criticized. Not mentioning sources is nowadays regarded plagiarism.

[5] Ibn Sina died in 1037 in Hamadan, Iran, probably of cancer. He was only 57 years old.

June 30, 2012 @ 17:28

Last modified July 1, 2012.

This entry was posted in Academics, Book Review, Iran, Medicine and tagged , , , , , , , , , , , , . Bookmark the permalink.

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