Definition of Jalonka ( Leeches ) – As the very basis of life for ‘Leeches’ is water, since their site of dwelling is ‘Jal’ i.e. water, the ‘Leeches’ are known as ‘Jaloka’.

Jalonka Avacharan( Leech therapy ) – In this method, Raktamokshan ( Blood letting ) is done with the help of ‘Leeches’ i.e. Leeches are applied on the desired site for blood letting. It is considered most unique & most effective method of blood letting. Here, the vitiated ‘Doshas’ are removed from the body without using any cutting instruments, hence Raktamokshan by means of ‘Leech’ comes under ‘Ashtra’ category.

Types of Jaloka Broadly Jalokas’ are divided into two types: – Poisonous (Savish Jaloka) Non- poisonous (Nirvish Jaloka ). Six different types of Leeches are found in both poisonous & non- poisonous category. Basically, these Jalokas are named according to their appearance i.e. their external look or color.
Poisonous – Krishna, Karbura, Algarda, Saamudrika, Indra- yudha, Gochandana Non- poisonous – Kapila, Pingala, Shankh- mukhi, Mushika, Pundarik- mukhi, Saa varika

Identification of Non- poisonous Leech – The Non- poisonous or ‘Nirvish Jalokas’ can be safely identified by their 1. Yellowish- Manhshila-like color 2. their swift activity 3. by their glitter like or copper like color 4. by their wide lotus- bud like mouth 5. by their glistening appearance. Generally, these Leeches are grown in pure flowing water, ponds with clean water & the lakes in which there are lotus flowers & greenery. 

Note: The poisonous Leeches are found in Muddy water, Gutters or in water which is contaminated by urine, stool, fish, frog & other water animals. They are comparatively bigger in size & dark in color. After the application they produce severe pain, itching or allergic reaction at the site, giddiness, fever, burning sensation, vomiting. Also few patient may develop signs of intoxication & sinking.

About Leeches – Scientific name: Hirudo medicinalis
• Country: Albania, Armenia, Austria, Azerbaijan, Belarus, Belgium, Bulgaria, Czech Republic, Denmark, Estonia, Finland, France, Georgia, Germany, Greece, Hungary, Ireland, Italy, Kazakhstan, Latvia, Lithuania, Luxembourg, Moldova, Netherlands, Norway, Poland, Portugal, Romania, Russia, Spain, Sweden, Switzerland, Turkey, Ukraine, United Kingdom, Yugoslavia
• Continent: Europe, Asia
• Diet: Blood of birds, fish, frogs, mammals
• Food & feeding: Carnivore
• Habitats: Freshwater

• Description: Leeches have segmented bodies like an earthworm, but unlike earthworms they are slightly flattened rather than round. They have a sucker at the head and the tail end and the one at the head surrounds the mouth. The mouth contains three jaws that can break the skin of their hosts to suck their blood. Medicinal leeches are greenish brown on their backs with thin red stripes running along the body and paler below. They grow up to 20 cm in length.

• Lifestyle: Leeches live in shallow muddy pools and ponds with plenty of waterweeds. When hungry, they attach themselves to a passing animal, break the skin with their jaws, and inject special chemicals that prevent the blood from clotting and reduces any pain. They then suck the blood of the host until they are full, when they withdraw their jaws and drop off into the water. They can consume 15 ml of blood – ten times their own body weight, before they are full, but they only need to feed every six months. 

• Family & friends: Like slugs, leeches are hermaphrodite, having both male and female parts, but they still need to come together to mate with each other.                  

• Growing up: After mating, 15-50 eggs are laid in a spongy case or cocoon, above the waterline often under stones. The eggs hatch in 3-5 weeks and the young leeches need two seasons of feeding before they are ready to breed themselves.

Specialty of Leech-
• A Leech has got an anti- coagulant chemical called Hirudin. While sucking the blood this Hirudin prevent clotting of blood.
• Ayurveda believes that Leeches suck only the impure part of blood. We can assume the sucking of blood from superficial veins which is deoxygenated or impure one.

• Hirudin – Inhibits blood coagulation by binding to thrombin
• Calin – Inhibits blood coagulation by blocking the binding of von Willebrand factor to collagen. Inhibits collagen- mediated platelet aggregation
• Destabilase – Monomerizing activity. Dissolves fibrin. Thrombolytic effects
• Hirustasin – Inhibits kallikrein, trypsin, chymotrypsin, neutrophilic cathepsinG
• Bdellins – Anti-inflammatory. Inhibits trypsin, plasmin, acrosin
• Hyaluronidase – Increases interstitial viscosity. Antibiotic
• Tryptase – inhibitor Inhibits proteolytic enzymes of host mast cells
• Eglins – Anti-inflammatory. Inhibit the activity of alpha-chymotrypsin, chymase, substilisin, elastase, cathepsinG
• Factor Xa inhibitor – Inhibits the activity of coagulation factor xa by forming equimolar complexes
• Complement inhibitors – May possibly replace natural complement inhibitors if they are deficient
• Carboxypeptidase A inhibitors – Increases the inflow of blood at the bite site
• Histamine like substances – Vasodilator. Increases the inflow of blood at the bite site
• Acetylcholine Vasodilator
• Anesthetics substances Anesthetic

Leech Therapy is used for –

• It is used effectively in the management of non- healing ulcerative lesions like Diabetic ulcer, Leprotic wound etc. as it helps to improve the local blood circulation. Hence, healing is promoted.
• It relieves vascular congestion. So, can be effectively used in conditions like long standing Varicose ulcers, Filariasis, post-operative skin grafting lesions
• It is used in Arthritis, Sprain or spasm to relieve the pain, inflammation & discomfort symptomatically
• Used in Abscess, Cellulites, Thrombophlebitis and Varicose Veins
• Useful in third degree thrombosed prolapsed Piles.
• Useful in Atherosclerosis of the limb as it improves circulation.
• Jaloka siddha oil is used locally to treat Hyper pigmentation, Erectile Dysfunction and Alopecia.
• Useful in various skin disorders like Eczema, Pimples, and Psoriasis etc.