Silver nitrate

Silver nitrate is a chemical compound with chemical formula AgNO₃. This nitrate of silver is a light-sensitive ingredient in photographic film and is a poisonous, corrosive compound. Silver nitrate crystals can be produced by dissolving silver in nitric acid and evaporating the solution. The compound notably stains skin a greyish or black color that is made visible after exposure to sunlight.

Silver nitrate has been used as an antiseptic, dropped into newborn babies' eyes at birth. This is to prevent contraction of gonorrhoea or chlamydia from their mother. A very weak solution is used for this, (about 1%) and there are very few side effects.

Mythically, silver nitrate was used as a method of killing vampires, with the silver nitrate generally being injected into a bullet cartridge or used in a hypodermic needle.

Fused silver nitrate, shaped into sticks, was traditionally called lunar caustic and used as a cauterizing agent.

It can also be used in wound management to 'knock back' over-granulation of tissue in healing wounds such as ulcers and sinuses.

AgNO₃ Cautery

Silver nitrate can be used in a medical environment as a chemical cauterizing agent and medicinal caustic. A typical applicator is composed of 75% silver nitrate with 25% potassium nitrate. As the silver nitrate contacts with water (in the blood) the compound goes into solution forming nitric acid. The acid subsequently is responsible for the cautery effect. As mentioned above this will typically result in a black or greyish staining of the skin. This staining is caused by the accumulation of the silver and will typically go away as the body rids itself of the mineral.