Leech Therapy- A Holistic Approach of Treatment in Unani (Greeko-Arab) Medicine

Abstract

The Unani System of Medicine also known as Greeko-Arab medicine, founded by Hippocrates is based on the concept of equilibrium and balance of natural body humours (blood, bile, black bile and phlegm). The imbalance in the quality and quantity of these humours leads to diseases whereas restoration of this balance maintains health of a person. The treatment methodology of diseases is based on four therapeutic modalities viz. Regimental therapy, Dieto-therapy, Pharmacotherapy and surgery. Irsale Alaq (Leech or Hirudo therapy) is one of the most important and widely practised methods of regimental therapy used for local evacuation of morbid humours. It is a procedure of treatment with the use of medicinal leeches. It has been suggested and successfully practised by Greeko-Arab physicians in the management of musculoskeletal diseases, gynaecological disorders, chronic skin diseases, thromboembolic diseases, varicose veins, ENT disorders etc since long. According to Unani doctrine, the efficacy of leech therapy is attributed to the analgesic and resolvent activities of leeches. However, from modern perspective, the saliva of leech contains about 100 pharmacologically active biological substances like Hirudin, hyaluronidase, vasodilators, anesthetics, antibacterial, fibrinases, collagenase etc. These substances are injected into human body while sucking of the blood and are responsible for the analgesic, anti inflammatory and anesthetic effects of leech therapy.

Introduction:

The name Unani is derived from a Greek word Ionian which means medicine a symbol of life. Tibb means the knowledge of the states of the human body in health and illness (decline of health). Unani Tibb strives to find the best possible ways by which a person can lead a healthy life. Hence, Unani is an age old, time tested system of medicine dating back 5000 years to Greece. It refers to a tradition of Greeko-Arabic medicine which is based on the teachings of Greek physician Buqrat (Hippocrates; 460-377 BC) and Roman physician Jalinoos (Galen) and developed into an elaborate medical system by Arab and Persian physicians such as Al Razi (Rhazes), Avicenna (Ibne sina), Al Zahrawi and Ibn Nafis. Unani is a form of traditional medicine widely practised in South Asia and draws on the ancient traditional systems of medicine of China, Egypt, India, Iraq, Persia and Syria. It is still popular in many Arab and East Asian countries. In fact Unani medicine and herbal products are gradually more being used in many countries where modern medicine is easily available. India has accepted it as one of the alternative health care system and has given it an official status.

Unani System of Medicine is based on the concept of Nazriya Akhlaat (Theory of Humours), given by Hippocrates, which supposes the presence of four body fluids- Dam (blood), Balgham (phlegm), Safra (bile) and Sauda (black bile) known as Akhlaat (Humours). As every person is supposed to have a unique humoral constitution, which represents his healthy state with a specific Mizaj (temperament), the Mizaj of a person is expressed as Damwi (sanguine), Balghami (phlegmatic), Safrawi (Choleric) and Saudawi (melancholic) according to the preponderance in the body. As long as these humours exist in normal quantities and qualities and in the normal region of the body, the healthy state of an individual is maintained. Any imbalance to the constitutions or changes in the quantity and quality of these humours result in diseases.[1,2]

In this system of medicine, the basic principle of treatment is Ilaj bil zid i.e treatment is in contrast to nature and Mizaj of the disease and is adopted in two ways i.e. observational and rational methods which are employed through diet, drugs, regimes, manipulation techniques and operations. Broadly speaking, there are four different methods of treatment viz; Ilaj bil Tadbeer (Regimental therapy), Ilaj bil Ghiza (Dietotherapy), Ilaj bil Dawa (Pharmacotherapy) and Ilaj bil Yad / Jarahat (Surgery).[3]

Ilaj bil Tadbeer is one of the most popular methods of treatment, practiced by ancient Unani scholars since antiquity. Literally Tadbeer is an Arabic word meaning regimen or systemic plan whereas Ilaj means therapy or treatment. Thus, Ilaj bil Tadbeer means treatment through regimen, which is a method, through which care of the sick person and maintenance of general health is attained through modulation or modification in Asbaabe Sitta Zarooriya (six essential factors for life). In other words, regimental therapies are mostly non medicinal techniques / procedures by which we modulate the life style, dietary habits and habitat of the patient and practise some other therapeutic regimens for the treatment of various diseases. The eminent Unani scholar, Ibne Sina has mentioned 36 regimes in his famous book “Canon of Medicine”. The important regimes include Irsale Alaq (Leeching), Fasd (Venesection), Ishal (Purgation), Qai (Emesis), Idrar (Diuresis), Huqna (Enema), Hijamat (Cupping), Dalak (Massage), Riyazat (Exercise), Hammam (Bathing), Tareeq (Diaphoresis), Amle Kai (Cauterization), Nutool (Irrigation), Inkebaab (Inhalation), Tanafis (Expectoration), Takmeed (Fomentation), Imala (Diversion of morbid material), Ilam (Counter Irritation), Aabzan (Hydration Therapy), Zimaad wa tila (Ointment and Liniment) etc. These regimes are actually meant for the Istefragh (evacuation) of Akhlate radiya (morbid fluids), from the body. These morbid humours true culprits responsible for the genesis of disease. As soon as these morbid humours are removed from the body, normal health gets restored.[4–6] Blood-letting in the form of venesection, leech therapy and cupping with scarification is an essential part of regimental therapy. It has been utilized for preventive as well as therapeutic measures for thousands of years by ancient Unani physicians.[7,8]

Irsale Alaq (Leech or Hirudo therapy) is a method of blood-letting which involves the withdrawal of blood in a considerable quantity from the body with the help of Leeches.[3] It is actually a blood sucking process with the help of medicinal leeches for prevention and treatment of various diseases. The therapeutic application of this therapy is known from the time of extreme antiquity and is still alive in present health scenario. The important advantage of leech therapy is that it may be advised on those areas of the body where other processes of blood-letting like venesection and cupping are not possible.[9,10]

HISTORICAL BACKGROUND

The use of leeches in medicine dates as far back as 3,500 years ago, when they were used for bloodletting in ancient Egypt. Leech therapy is one of the oldest medical practices, having been practiced among the diverse ancient people, including the Mesopotamians, the Egyptians, the Greeks, the Mayans and the Aztecs. In Greece, Leech therapy was first introduced by a famous Unani physician, Hippocrates, also known as father of medicine. The popularity of this therapy was reinforced by the ideas of Roman philosopher Galen, who classified Leech therapy as a method of treatment and prevention of health. He believed that blood was the dominant humour and the one in most need of control. In order to maintain the balance of humours, a physician would either remove excess blood from the body or advise them any other treatment for evacuation of morbid humours. When Islamic theories became known in the Latin speaking countries of Europe, Leech therapy became more widespread. Together with venesection, it was central to Arabic surgery, which is mentioned in classical Unani literature; “Alqanoon fil tib” and “Altasreef liman Ajeza Anittalif”. It was also known in Ayurvedic medicine, described in Sushruta samhita. Dhanvantari, the Indian god of Ayurveda holds a leech in one of his 04 hands. The practice of this therapy continued throughout the middle Ages but began to be questioned in the 16^thcentury, particularly in northern Europe.[7,11] In 1980, medicinal leech therapy got a big boost by plastic surgeons, who used leeches to relieve venous congestion especially after skin grafting in transplant surgery. This use of leech therapy provides a good example for its current status. When appendages are reattached following traumatic amputation, it is often possible to reconnect the larger arterial blood vessels, but not the thinner more delicate venous vessels. The body will eventually develop the necessary venous connections to drain the area of oxygen-depleted blood but if this does not occur rapidly enough, pooling of venous blood can produce enough swelling and pressure with which fresh arterial blood may no longer be able to enter the re-connected limb. In this situation, leeches are used to drain the local blood and decompress the pressure within the grated limb otherwise, a risk of necrosis develops as a complication.[12,13]

Contemporary leech therapy was pioneered by the surgeons, M Derganc and F Zdravic, who elucidated the use of leeches in tissue flap surgery in which a flap of skin is freed or rotated from an adjacent body area to cover a defect or injury. Their rationale behind the use of leeches was based on a unique property of the leech bite, namely, the creation of a puncture wound that bleeds for hours. Today medicinal leeches are used in the treatment of various diseases such as thrombophlebitis, hypertension, varicose ulcer, skin and musculoskeletal diseases.[7,12–15]

DESCRIPTION OF LEECHES

Leeches are carnivorous or blood sucking annelid worms with pronounced ability to extend or contract their bodies. They are hermaphrodite in nature and are distributed all over the world, except the polar zones, deserts and altitudes exceeding 3,700 m. In India, about 45 species belonging to 22 genera occur.[16] The common Indian species are Hirudinaria granulosa, H. viridis, H. javanica, and H. manillensis. These species are also common in Burma, Pakistan, Bangladesh and Sri Lanka. Haemadipsa is a land leech of the hills of Southern India.[17]

The medicinal leech (Hirudo medicinalis) is a European species which has been introduced into certain ponds and streams of the eastern portion of the United States. It is relatively large leech often growing to 10 or more centimeters in length. It feeds upon blood of a vertebrate to which it periodically attaches itself.[18] Among Indian leeches, Hirudinaria granulosa has got medicinal properties. It is a common leech found in freshwater tanks, ponds lakes, swamps, and slow streams. It prefers shallow water and remains concealed under weeds, logs and stones. It is sanguivorous (blood-sucking), sucking the blood of fishes and frogs and also of cattle or human beings when they enter the pond.[17–19] It is abundantly found in the states of Tamilnadu, Kerala, Madhya Pradesh, Uttar Pradesh and Punjab.[16,20]

Leeches are blood sucking worms with segmented bodies and belong to the same large classification of worms as earthworms. These can primarily be found in freshwater lakes, ponds or rivers ranging from 5mm to nearly 25 cm and have two characteristic suckers located at either end of their bodies. To feed, a leech first attaches itself to the host using the suckers. One of these suckers surrounds the leech's mouth, which contain three sets of jaws, each consisting of about 80 calcareous teeth that bite into the host's flesh, making a Y-shaped incision. Between the teeth, lie little openings through which the saliva is secreted. As the leech begins to feed, its saliva releases chemicals that dilate blood vessels, decreases the blood viscosity and deaden the pain of the bite.[15,21]

CLASSIFICATION OF LEECHES

For the purpose of therapeutic application, Unani scholars have classified leeches into poisonous leeches and non poisonous (useful) leeches on the basis of specific characteristics. The features of therapeutically useful leeches are leeches with thin tiny head, emerald green colour, tiny and rounded like rat's tail and leeches found in moist rich places where frogs are in abundance. Leeches with long head, black, grey or green colour are described as poisonous.[22,23]

PROCEDURE OF LEECH THERAPY

The legendary Unani scholar, Ibne Sina in his famous treatise “Canon of Medicine”, an encyclopedia of medicine which served as a standard text book of medicine in Europe till 17^th century A.D, has described the procedure of Leech therapy in a very comprehensive manner and narrated the following steps of the whole procedure:[1–3]

1. Pre-leeching procedure involving collection of leeches; preservation of leeches and selection of suitable patient.

2. Leeching Procedure Proper

3. Post-leeching Procedure involving separation of leech; vomiting of leech and control of bleeding.

Ibne Sina narrated that leeches should be collected just one day prior to their use. Patient is advised to take light semi-solid diet prior to the procedure. The affected part to be treated is thoroughly washed with distilled water or with a solution of borax and rubbed until redness appears. If the leech is reluctant to attach, a tiny droplet of blood may be smeared on the part to be treated and then leech is applied. Usually, one or more leeches are applied to the affected area and left for half an hour. Once the leech is attached, it will likely remain safely in place until fully distended but it is essential to check the site continuously to insure that the leech hasn′t separated. Thereafter, the leeches are detached with a very careful manner by pulling them off or by loosening their grip with table salt, borax or heat but sometimes leeches detach automatically. The used leeches are then killed and disposed off.[1–4]

MECHANISM OF ACTION

According to the Unani doctrine, leech therapy works on the principles of Tanqiyae Mawad (Evacuation of morbid humours) and Imalae Mawad (Diversion of humours). Tanqiyae Mawad means the resolution and excretion of morbid humors and excess fluids from the body, thereby maintaining the homeostasis in the quality and quantity of four body humors, which is actually responsible for the maintenance of normal health. Imalae Mawad refers to the diversion of the morbid fluids from the site of affected organ to the site where from it is easily expelled from the body tissues. Based on this holistic approach, Unani physicians have been widely using this therapeutic regimen for a number of diseases. The effectiveness of this therapy may also be attributed to the Mussakin (sedative) and Muhallil (anti-inflammatory) actions of saliva of leeches.[3,4,9]

However, from modern perspective, as proved by various research studies, the efficacy of leech therapy lies not in the amount of blood that leeches ingested, but also in the anticoagulant enzymes of the saliva that allow blood to flow from the bite after the leech is detached. Moreover, the saliva of leech contains about 100 pharmacologically active biological substances which contribute to the special property of leech. These include anticoagulants like hirudin, calin, inhibitors of kallikrein, hayaluronidase, histamine-like vasodilators, collagenase, and poorly characterized anaesthetic and analgesic compounds.[19,14] Hirudin is responsible for inhibiting blood coagulation and is employed as an anticoagulant in surgical operations and has been recommended for the prevention of phlebitis and postoperative pulmonary inflammation. Calin also inhibits blood coagulation but it is responsible for slow cleansing of wound by maintaining secondary bleeding for approximately another 12 hours. Histamine-like substances have dilating effect on the blood vessels and thereby cause the blood to stream to the bite site. In the mean time, the spreading factor, hayaluronidase acts to clear the path for the active and healing substances to penetrate. These substances allow continued bleeding for up to 24 hrs after the leech has been detached. Besides, a regional analgesic and antiphlogistic effect by these substances enforced by hayaluronidase as well as counter irritation might be possible.[13,15,24] Furthermore, some of these substances have anti-inflammatory and other additional effects like lipotropic activity that can be used at atherosclerotic defects of vessels in ischemic heart disease and diabetes mellitus. The existence of skin visceral connections with the definite organ is well known. Through veins, the biologically active substances act on organ during sucking by leech. It promotes the improvement of blood circulation in the organ, renders thrombolytic, anti-inflammatory and immuno-stimulant action.[20,24] Leech therapy reduces pain, stiffness, and joint dysfunction in people with osteoarthritis of the knee as reported by a new study in the Annals of Internal Medicine.[25]

INDICATIONS

Leeches were thought to be able to cure everything from head ache to hemorrhoids. Ancient physician used to treat chronic skin diseases, eye diseases, musculoskeletal diseases, gynaecological disorders, ENT disorders, thromboembolic diseases, local congestive condition, as well as brain congestion and mental illness. The commonest indications of Leech therapy as mentioned in Unani classics are Jarabul Ajfaan (Blephritis), Dawali (varicose vein), Darde pindali (Painful Calf muscle), Malankhoonia (Mania), Qooruhe khabisa (septic wound, non-healing ulcer), Warm (inflammation) of organs, Khanaazeer (Lymphadenitis) , Warme Tajaweful Anaf (sinusitis), Warme halq (Pharyngitis), Bawaseer (Piles), Nawaseer (Fistula in ano), Daaul feel (Elephantiasis), at the biting site of poisonous animals, skin disorders like Qooba (Ringworm) , Saafa (Tinea corporis), Namash (Chloasma), kalaf (Warts), Narfarsi (eczema), Daul sadaf (psoriasis), Bars (Vitiligo), Wajaul Mufasil (Osteoarthritis), hypertension etc.[3,4,26–28] Nowadays use of leeches in thromboembolic diseases (coronary artery thrombosis and Ischemic heart diseases), plastic surgery, replantation and other reconstructive surgeries is very famous all over world.[12]

CONTRAINDICATIONS

Leech therapy is contra indicated in the treatment of certain medical conditions and diseases. These include hemorrhagic diseases, absolute hemophilia, pregnancies, severe anemia, hypotension, general fatigue, allergy to leech, active tuberculosis, mental disorders during acute episode, high temperature, immuno compromised patients, severely ill & bed ridden and in case of extremely fearful patients. According to some Unani physicians, certain sites of the body are also contra indicated for the leech application such as abdomen especially around the liver, spleen, stomach, intestine and buttock. In tropical areas, leech therapy has been prohibited as the site of leech may become infected.[4,22]

ADVERSE EFFECTS

In spite of all the precautions taken, there is a risk of certain adverse effects and subsequent complications such as pain during treatment, local itching, hypotension, vasovagal attacks, anemia, super infections, allergies, sepsis, transmissions of infectious diseases, scarring and slight fever.[15,16,21]

SCIENTIFIC REPORTS

In recent past years, various clinical as well as experimental studies have been conducted globally to evaluate the efficacy of leech therapy in various ailments using standardized outcome measures. The leeching has proved very beneficial in microsurgeries and different types of arthritis.[29] In a study conducted in Germany, the effectiveness of leech therapy in osteoarthritis of knee was established. The patients (n = 51) received a single sting of leeches (4 to 6 in number). The primary end point pain at 7^th day was reduced from 53.5±13.7 to 19.3±12.2 in leeching group compared to the control group where the pain was reduced from 51.5±16.8 to 42.4±19.7 with topical diclofenac application.[25] In another study, the hirudin was tested for thrombin inhibition in synovial inflammation in Antigen Induced Arthritis (AIA). The study was conducted on animal models where experiments showed hirudin did indeed significantly attenuate the severity of AIA as measured by both ^99mTC uptake and synovial histology. The intra-articular fibrin staining was reduced by hirudin treatment. There was a clear reduction seen in synovial inflammation by hirudin.[30] The hirudin as a potential therapeutic agent for arthritis has also been advocated by K Scott, Professor in University of Auckland, New Zealand[31] and synovial stimulatory protein (SSP) acting as auto-antigen, to which T-Lymphocytes from patients with rheumatoid arthritis respond, identified in synovial fluid has been found to bind to a hirudin-agarose affinity chromatography matrix.[32]

In India also, various studies have been conducted to prove the safety and efficacy of leech therapy in musculoskeletal and dermatological disorders on the basis of scientific parameters. A study from Kashmir valley, India has established the safety and efficacy of leech therapy in the management of frostbite.[33] Another study from Bangalore India, has proved the safety and efficacy of leech therapy in the management of knee osteoarthritis (OA). In this study, 30 diagnosed patients of knee OA were subjected to leech therapy and the efficacy assessment was done weekly with the help of Western Ontario and McMaster University (WOMAC) OA Scale and Visual Analogue Scale (VAS) Score. After the completion of treatment of one month, these scores were reduced significantly (p<0.05), thereby proving the efficacy of leech therapy in OA.[34] Similarly one more study from India has proved the significant effect of leech therapy in the treatment of varicose ulcers.[35]

CONCLUSION

It can be concluded that leech therapy has unique features that are easily recognized. It can be used effectively for the management of various disorders specially skin and musculoskeletal disorders where western medical treatment is of less value. It may be used for the restoration of normal heath through its prophylactic and palliative action. It may produce better results either singly or as an adjuvant with drug therapy in diseases like hypertension, thrombosis, atherosclerosis, arthritis, varicose veins, frostbite, skin diseases like dermatophytosis, psoriasis, eczema, vitiligo and in various surgical and traumatic conditions such as re-attachment of severed extremities, fingers, toes and ears. However authors suggest that it is the need of present era to develop standard operative procedures (SOP'S) and scientific parameters so that the efficacy of leech therapy can be proved in a rational manner.