Health benefits of pendant from the viewpoint of Persian medicine

Background: Reviewing historical evidence in the various schools of traditional medicine shows that numerous methods have been used to maintain human good health and treatment of diseases. Persian medicine (PM) scholars have been employed different methods to prescribe medications, which can be classified into two main groups: internal uses, including oral, parenteral, and anal, and also external uses such as topical, transdermal, and applying pendants. In this study, we aim to introduce some of the therapeutic pendants. Methods: We reviewed the most famous PM textbooks and current evidence in relevant databases such as PubMed, Science Direct, Scopus, Google scholar and SID related to the topic. Results: In this study, about 100 traditional therapeutic substances were found and finally, thirty-two of them were represented. They were often stones, and some of them were other materials such as metals, gums, and herbs. According to the PM, the utilization of pendants, in addition to cosmetic purposes, has been considered to maintain the health and treatment of some diseases. Therapeutic pendants can be considered as a kind of external medication use in which therapeutic materials are hung on the body surface. The external use of pendants could have curative effects with their close contact to the body surface. Conclusion: Pendant therapy may probably be considered as a non-invasive and easy-to-use treatment with unnoticeable side effects that can be utilized along with other therapies.


Introduction
Humankind has been used various methods to treat diseases since ancient times. Historical evidence shows that Persian medicine (PM) scientists have also been experienced a number of methods to create a therapeutic effect [1]. PM as one of the firstborn schools of medicine has a holistic viewpoint to the health care, prevention and treatment of diseases with several thousand years of history [2]. According to the PM manuscripts, medicaments with herbal, animal and mineral origin have been practiced in solid, semisolid, liquid and gaseous forms. PM scholars have mentioned different types of dosage forms for these natural medicaments in their pharmacopeias and medical textbooks. They have been applied in desired doses by oral, topical, nasal, parenteral, vaginal and rectal routes of administration for related therapeutic purposes [1,3].
Oral administration is one of the most common stated routs of administration with systemic effects [3]. However, there are other routes of administration without direct ingestion such as aromatherapy [4]. One of the common forms of external medicinal use is wearing or hanging of mineral (stones), plants, gums, etc. that can be utilized along with other therapies. This kind of drug delivery is called "Ta'līq" in Arabic and "Awīzeh" in Persian, which is equivalent of pendant in the current nomenclature. They were employed as necklace, earring, bracelet, and ring either alone or in combination with other herbal, animal and mineral ingredients in the treatment of a wide variety of diseases. In order to take advantage of their beneficial effects in some cases it is enough to put on the surface of a sick or damaged organ or to be placed only in the person's living environment [5][6][7][8].
Historical evidence from ancient civilizations shows several thousand years' history of using stones for releasing mental, physical and spiritual problems through balancing emotional and spiritual aspects of the body to enhance the health. Sometimes stones were used to protect people from disasters such as wars or even natural disasters [9,10].
The books "Al-Jamāhīr fī Ma'rifat al-Jawāhir" (The Book Most Comprehensive in Knowledge on Precious Stones) by Abu Rayḥān Muḥammad ibn Aḥmad al-Bīrūni and "Tansūkh nāmeh Ilkhānī" by Nasīr al-Din Muḥammad ibn Muḥammad Ṭūsi are the two valuable ancient references of mineralogy and gemology in Iran, which demonstrate the interest of ancient Iranian scholars to gemstones and their Health benefits and therapeutic properties [11,12]. Gemstone therapy is a well-known, non-invasive and easy-to-use complementary and alternative medicine (CAM) practice with unnoticeable side effects that includes wearing precious and semi-precious stones in order to improving individual's physical and emotional health. Nowadays, there is a common belief among the people that the use of gemstones is effective in maintaining health and even treating various ailments [13,14].
To the best of our knowledge, this concept has not been suitably studied from the viewpoint of PM. Considering the tendency of the general population to use CAM for the treatment of diseases and the scattered evidence of the healing effect of gemstone pendants as a complementary medicine, we aimed to introduce the pendants and their health benefits in the PM.

Materials and methods
In this study, we reviewed several main PM textbooks including Al-Qānūn fī al-Tibb (the Canon of Medicine) by Avicenna (11th century), Exīr Azam by Azam Khān Chishti (19th century), Khulāsat al-Hikmat by Aghīlī Shīrāzī (18th century), Tibb Akbari, and Mīzān al-Tibb, by Arzāni (late 17th and early 18th century) and the most comprehensive traditional medicine pharmacopeias such as Makhzan al-Advyyah by Aghīlī Shīrāzī and Qarābādīn Azam by Azam Khān Chishti to collect data from medieval medical textbooks. The search was performed according to the keywords of "Tā'līq", "Avīzeh" and their derivatives. Those medicaments with mineral, plant and animal sources used as pendant were gathered. Then health benefits of pendants in preventive care and their application in the treatment of diseases of the human body were categorized. Furthermore, electronic databases such as PubMed, Science Direct, Scopus, Google scholar and SID were searched from 7 June 1990 to 26 May 2021 related to the topic. The search terms were "pendant", "gemstone", "stone medicine", or "gemstone therapy" and "health", "disease", "treatment", "herbal medicine", "plant", "herbal", "mineral", "traditional medicine" or "complementary medicine" without narrowing or limiting search items. Relevant publications with available abstracts and titles were reviewed.

Results
From the perspective of PM, health care system is based on three main pillars, including lifestyle modifications, medications, and manual therapies [6,8]. In PM textbooks, there are different types of dosage forms some of them include oral, topical, nasal, ophthalmic, vaginal and rectal routes [5]. The use of pendants has been considered as one of these methods [5][6][7][8]15]. Pendants had a wide range of uses, including ornamental purposes and to maintain individual's health. Moreover, pendant was a pharmaceutical dosage forms in PM textbooks, which is utilized as a rout of administration followed by other treatment strategies for several ailments. PM scholars explained several plant-, animal-, and mineral-derived pendants, which originated from stone, metal, all or part of a plant or animal, gum, and soil [5,16].
In this study, more than 100 materials (minerals and non-minerals) were found in PM manuscripts, which have also been used as pendants. Then their old and traditional names were matched with the present common names, only 32 of them had a present equivalent name, and among those which were easier to access and use at the present time were selected and declared. Table 1 shows examples of medications were used individually as pendants with their common names, traditional names, and health benefits and therapeutic properties.
Pendants were employed in the form of necklaces, wristbands, earrings, bracelet and ring and armbands. In some cases, it was enough to be placed on a specific part of the body, such as the neck, wrists, thighs, and even held in the hand. Some of them were also hung in human habitats to show their effects on maintaining health or treating disease. The type of pendant and its place in the body are determined based on the expected therapeutic effects. For example, jasper stone when placed on the neck, can be effective for pharyngitis (Xonāq), when placed on the left upper chest, it is useful in controlling palpitation. Using it as a pendant near the esophagus and stomach strengthens them (gastric tonic). Pulling jasper around the thighs useful for labor difficulty and can speeds up labor.
There is a belief that jasper stone can help to protect witch craft, evil eyes and lightning strike damages too [5-8, 11, 12, 15, 16]. It has also been noted that the properties of the stones change under certain conditions. For example, if a lodestone is placed in olive oil or milk, its magnetic property is damaged, while washing it with vinegar restores this property [11]. Some criteria have been considered for choosing a gemstone as a pendant. The Items such as being aromatic, having the ability to engrave and even the color of the string used by the gemstone are important factors in choosing a gemstone as a pendant, especially for its therapeutic effects.

Discussion
Nowadays, CAM has become increasingly popular. The high cost of conventional treatments and the failure to achieve optimal healing outcomes in some cases are the two highlighted causes of the general public's tendency toward CAM [17,18]. Homeopathies, Ayurveda, aromatherapy, acupuncture or gem therapy are some examples of complementary medicine branches [19]. Gemstone therapy as a kind of pendant therapy, is a holistic, non-invasive method in which stones with specific colors and radiations exert certain properties and energies that affect the body's physical and emotional health [20]. Submit a manuscript: https://www.tmrjournals.com/psmr The placement of these stones in specific areas of the body is important for exhibiting their therapeutic effects, as it is essential for Chakra therapy to place stones in the place of the chakra [14].
Although a great deal of information about stone therapy is available on different websites, evidence-based medicine on its therapeutic effects is limited and there are few reliable clinical trials on this subject. Natural stones are advertised as "healing tools" and this is effective in favoring their use with the hope of healing. Therefore, when people around the world use healing stones, the placebo effect can be seen [21]. In gem therapy as another form of pendant therapy, gems such as emerald could be effective for those ailments healing. In contrast, Assimilator of swelling diseases such as diabetes, cancer, hepatitis and multiple sclerosis require increasing energy and heat induction in their treatment process, and then gemstones such as rubies and diamonds may be useful [14]. Although, there is not enough scientific evidence that shows the relationship between gemstones chemical compositions or their colors and the healing effects of them on a particular ailment, gem therapy has still remained popular in many countries such as Pakistan. They use these stones through different methods including in the form of pendants such as wearing necklaces and earrings, as well as other ones such as wearing rings, wristbands and arm bands [14].
According to the PM (as one of the branches of CAM), the use of pendants is considered a preventive care and treatment strategy as well. In addition, various types of pendants have been used for decorative purposes among the people. In this treatment, pendants with animal, plant and mineral origin are in contact with a part of the body's surface for a certain period of time [5,6].
Some minerals, whether taken orally or in the form of a pendant, have therapeutic effects. For example, the use of lapis lazuli in combination with oral medications can have many therapeutic effects, including strengthening the heart. Its cardiac tonic effect can also be seen when wearing lapis lazuli as a necklace. Some of the pendants are also fragrant, so their aromatic properties are used for permanent and long-lasting therapeutic effects.
Some of these materials have a special effect only in the form of pendants. For example, Coriandrum Sativum L. (coriander) can only to be useful in the labour progression if it is tied around the thigh. This therapeutic effect is not mentioned in other methods of using this plant. Moreover, in PM textbooks it is mentioned that some pendants should be placed on the target organ such as the heart and in close contact with the organ to show the desired therapeutic effect. Therefore, therapeutic properties of these drugs appear only to be present as a pendant and in close contact with the skin [5][6][7][8]15]. Depending on the disease and the purpose of the therapist, the stones are placed on specific part of the body surface such as energy channels or chakras [14].
Due to the lack of scientific papers and clinical trials in the field of pendant therapy, our findings represented an attempt to provide a basis for more research about pendants beneficial in medicine, pharmacy and even medical engineering. In spite of the abundance stone mines in our country Iran, it is better to know the healing properties of these stones and utilize them in the treatment of diseases. Another important feature of this article was the introduction of the other therapeutic pendants such as metals, plants, gums and animals' material which showed that therapeutic pendants are not limited to the stones.
One of the limitations of our study was that many of the materials we found in PM textbooks were named with their old Persian names, and we did not find their today's name equivalent, the other limitation was that some of the materials we found in the ancient texts were unconventional in present-day use so we omitted them and declared only the materials that had present equivalent names.

Conclusion
According to the findings, it seems that the use of therapeutic pendants such as stone, herb and metal is a method of administering medications that affects externally. Applying this method has its own rules, such as choosing the right material and the right place to hang or put to reaching its beneficial effects in improving the health of patients along with the other treatment methods.