What it is:
This herb is a crystalline compound derived by distilling the tree trunk of Dryobalanops aromatica Gaertn. f. (family Dipterocarpaceae) and then cooling the distillate. The herb obtained in this way is called Longnao or Mei borneol (Dryobalanops borneol). Now borneol is mostly synthesized chemically form turpetine oil or camphor. This kind or borneol is called machine-made borneol. Borneol can also be made from the sublimate of the leaves of Blumea balsamifera DC. (family Compositae), stored in air-tight containers in a dark cool place. It is ground to powder for use.

Property:
Flavour and channel tropism: pungent and bitter in flavour, slight cold in property, action on the heart, spleen and lung channels.

Used for:
1. Phlegm syncope, apoplexy, coma, convulsion and so on. It is usually used with musk, as in cow-bezoare Bolusfor Resurrection (Angong Niuhuang Wan) and Treasured Bolus (Zhibao Dan).

2. Swollen and sore throat, canker sores, blood-shot, swollen and painful eyes, sores, ulcers, etc. For the treatment of swollen and sore throat, it can be used with borax, cinnabar and dried galuber's salt, i.e., borneol and Borax Powder (Bing Peng San); to treat blood-shot, swollen and painful eyes, it can be given with coptis and calamine,as in Nebula Removing Powder (Boyun San). In addition, it is used in many compound recipes for clearing away heat and promoting regeneration of tissues.