Leech saliva contains a protein that is known scientifically as hirudin which is an active anticoagulant component. Hirudin is a natural inhibitor that was discovered and isolated using recombinant technology. This is a key element that is both a natural inhibitor.

Hirudin has the potential to prevent or dissolve formation of blood clots. It also has a therapeutic value in healing blood disorders, treatment of skin diseases and varicose veins.

This is one of the many key elements that is extractable from leeches. Although traditional methods are nothing compared to recombinant technology, traditional healers have known the many benefits from this creature.The benefit from this little worm as some know it is extracted through a simple extraction method by boiling the hand caught leeches with other herbs and letting it become thick and oily. In certain countries in Asia, this oil is bottled as (leech oil) and sold as it is.

Interestingly leech has been a property used even in ancient times. Records encrypted from hieroglyphics painted on pyramids indicate pictures of leeches. Leech was an ingredient used in the treatment of headaches, hemorrhoids, and bloodletting. Bloodletting is a process of removing blood from patients. In ancient medicine, it is believed that there are four humours which is blood, phlegm, black bile and yellow bile. If these four humour was kept in balance the body would function properly. If one of these four humour is imbalanced, this could be the cause of many illnesses. By letting the blood out or bloodletting, all the excess or impure blood is removed from the patient and heals them. Throughout the generation, leech and leech oil has been used by natural healers to treat many diseases. This shows how minyak belacak (leech oil) is a natural remedy and has the properties to still be a strong traditional medicine to be used until this day.