ne of the most important types of parasitic diseases is worm infestation which is usually chronic and causes many physical and economic problems, anemia and problems in the growth and height of children. In previous years, this disease were mainly found in tropical regions of the world such as India and South Africa, but today, due to the increased travels and communications between different communities, trade and food exchanges, the creation of a global village, drinking water pollution in many areas, climate change and warming of some geographical areas, urban sprawl, keeping animals in small apartments, and the problems with garbage disposal and wastes has increased the prevalence of this disease.
Many different types of worms have been identified so far that can cause disease in humans and their life cycle and pathogenesis vary in different geographical areas. They are generally divided into three main groups: Round worms (nematodes), tape worms (cestodes) and trematodes. These worms lives in different the parts of the body. Nematodes are cylindrical and filamentous parasites that vary in length from 1 mm to about 1 m. Some nematodes, such as Ascaris and pinworm, live in the gastrointestinal tract and are known as intestinal nematodes. Some cause disease in connective tissue and some in other parts of the body. So far, more than 32 types of worms have been identified in Iran, which are human parasites. The most common reported worms are Ascaris (in Isfahan, Khorasan, Azerbaijan), hookworm (in the northern regions and Khuzestan) and trichostrongyloids (in Isfahan and some southern regions).
Historical documents have shown the knowledge of diseases caused by parasitic worms from 3000 years ago. According to the writings on clay tablets, mint, coriander, onion, some kinds of gum, floss and pomegranate bark have been used as anti-worm substances in different regions. In the books of Iranian Traditional Medicine (ITM) scholars, parasitic diseases are mentioned under the general title of “Didan”, and various drugs and treatment methods for this disease are introduced. Many Western scholars have also referred to the findings ITM scholars in their books. The first book on medical wormology from the perspective of classical medicine was written in 1668 by William Ramsay, an English physician. In the late 16th century, with the invention of the microscope, the life cycle and pathogenicity of worms were identified and divided into different groups. The use of chemical drugs against worms and parasites began in the early twentieth century and has continued to this day. The most important complications of these drugs are neurological side effects (e.g. seizures, headache, dizziness, muscle weakness) as well as teratogenic and allergic effects and intestinal obstruction. Increase in the elderly population, life expectancy in people with underlying diseases and immunodeficiency, resistance to antiparasitic drugs and serious side effects of these drugs require more investigation and testing to maximize effectiveness and minimize damage.

In this study, we collected data by using library method and review of the sources of modern medicine and the materials related to parasitic diseases in the Canon of Medicine book of Avicenna (one of the most glorious written works of ITM) for three months. In order to investigate the data related to the treatment of parasitic diseases, we reviewed ITM books such as Canon of Medicine, Eksir-e-Azam, Kholasat al-Tajarob, Zakhireye Khwarazmshahi, Kholasat al-Hekmat, Kitab al-Mansouri, Makhzan al-Adviah, Grabadin-e Kabir, Al-Aghraz al-Tibbia, Tebbe Akbari, Mofrah al-Gholob, Dagaiegh al-Alaj, Al-Shamel, Tohfah al-Momenin, and Sharh al-Asbab va al-Alamat, by using keywords “Kerm”, “Dod” and “Didan”. After collecting data, they underwent content analysis and then were formulated.

The findings showed that the treatment of parasitic diseases in Avicenna’s Canon of Medicine follows a model based on rational drug administration. Content analysis of the extracted materials showed that Avicenna’s approach in the treatment of parasitic diseases is based on the problem-solving model according to the patient’s condition in terms of severity and prioritization of the following factors, and varies from person to person: A. Underlying causes of parasite nutrient production in the body; B. clinical symptoms (Table 1);



C. Patient-related causes such as patient’s general mizaj, gastrointestinal organ temperament, strength and weakness of the patient based on pulse and underlying diseases, and patient’s age, habits and lifestyle; D. Properties of drugs such as temperament of anti-parasitic drugs, ability to kill and expel parasites, ability to strengthen the stomach and digestion; E. Time and method of drug administration: orally, by injection, by inhalation, topically, and in suppository form; F. Type of parasite, diagnosed based on clinical symptoms and observation of the parasite itself (Table 2).

Drugs introduced in the books and sources of Iranian medicine as a medication affecting parasitic diseases can consider all the mentioned microorganisms and worms and have a range of different therapeutic effects on other organs; thus, the destruction of parasites has been considered. Given the increasing prevalence of various emerging and immunological diseases in human societies, the need for a new approach to parasitic diseases and clinical trials seems necessary. The book "Observing the Principles of Hygiene", along with diagnostic and therapeutic methods of classical medicine, can be effective in controlling and preventing this disease; even in many cases, based on the patient's set of clinical symptoms, herbal medicines can be used to treat parasitic diseases.

All ethical principles are considered in this article. The participants were informed of the purpose of the research and its implementation stages. They were also assured about the confidentiality of their information and were free to leave the study whenever they wished, and if desired, the research results would be available to them. A written consent has been obtained from the subjects. principles of the Helsinki Convention was also observed.

This research did not receive any grant from funding agencies in the public, commercial, or non-profit sectors.

Both authors equally contributed to preparing this article.

The authors declared no conflict of interest.

Both authors would like to thank Nastaran Niknafs for her cooperation.