Properties : Sodium thiosulphate occurs as colorless, transparent monoclinic prisms, odorless and having a cooling, afterward bitter taste. It is very soluble in water (1 :05) and practically insoluble in alcohol.

Incompatibilities: Sodium thiosulphate is incompatible with acids, iodin and chlorin. It dissolves insoluble salts of silver.

Action and Uses: Sodium thiosulphate is used externally, in the form of a lotion, as an application for ringworm and other parasitic skin diseases. It is extensively used in photography and has been given internally in place or sodium sulphite. It may be used to remove stains of iodin, silver nitrate, etc.

Dosage: 1 gm. or 15 grains. It may be used in aqueous solution or ointment of 10 per cent, strength or 1 dram to the ounce.