Silver Nitrate

(rINN)

💊 Chemical information

Argent, nitrate d’; Argenti nitras; Dusičnan stříbrný; Ezüst-nitrát; Gümüş Nitrat; Hopeanitraatti; Nitrato de Plata; Nitrato de Prata; Plata, nitrato de; Sidabro nitratas; Silvernitrat; Srebra azotan.
Chemical formula: AgNO3 = 169.9.
CAS — 7761-88-8.
ATC — D08AL01.
ATC Vet — QD08AL01.

Pharmacopoeias.

In Eur., Int., Jpn, US, and Viet.

Ph. Eur. 6.2

(Silver Nitrate). A white or almost white, crystalline powder or transparent colourless crystals. Very soluble in water; soluble in alcohol. Store in nonmetallic containers. Protect from light.

USP 31

(Silver Nitrate). Colourless or white crystals. On exposure to light in the presence of organic matter, it becomes grey or greyish-black. Soluble 1 in 0.4 of water, 1 in 0.1 of boiling water, 1 in 30 of alcohol, and 1 in 6.5 of boiling alcohol; slightly soluble in ether. Its solutions in water have a pH of about 5.5. Store in airtight containers. Protect from light.

Incompatibility.

Silver nitrate is incompatible with a range of substances. Although it is unlikely that there will be a need to add any of the interacting substances to silver nitrate solutions considering its current uses, pharmacists should be aware of the potential for incompatibility. The reported yellow-brown discoloration of samples of silver nitrate bladder irrigation (1 in 10 000) probably arose from the reaction of the silver nitrate with alkali released from the glass bottle which appeared to be soda-glass. 1 1. PSGB Lab Report P/80/6 1980.

💊 Adverse Effects

Symptoms of poisoning stem from the corrosive action of silver nitrate and include pain in the mouth, sialorrhoea, abdominal pain, diarrhoea, vomiting, coma, and convulsions. Short-term mild conjunctivitis is common in infants given silver nitrate eye drops; repeated use or the use of high concentrations produces severe damage and even blindness. Chronic application to the conjunctiva, mucous surfaces, or open wounds leads to argyria (see Silver, above), which though difficult to treat is mainly a cosmetic hazard. Although silver nitrate is not readily absorbed, absorption of nitrite after reduction of nitrate may cause methaemoglobinaemia. There is also a risk of electrolyte disturbances.

Effects on the eyes.

Silver nitrate from a stick containing 75% was applied to the eyes of a newborn infant instead of a 1% solution.1 After 1 hour there was a thick purulent secretion, the eyelids were red and oedematous, and the conjunctiva markedly injected. The corneas had a blue-grey bedewed appearance with areas of corneal opacification. After treatment by lavage and topical application of antibacterials and homatropine 2% there was a marked improvement and after 1 week topical application of corticosteroids was started. Residual damage was limited to slight corneal opacity.
1. Hornblass A. Silver nitrate ocular damage in newborns. JAMA 1975; 231: 245.

💊 Uses and Administration

Silver nitrate possesses antiseptic properties and is used in many countries as a 1% solution for the prophylaxis of gonococcal ophthalmia neonatorum. However, as it can cause irritation, other drugs are often used. In stick form it has been used as a caustic to destroy warts and other small skin growths. Compresses soaked in a 0.5% solution of silver nitrate have been applied to severe burns to reduce infection. Solutions have also been used as topical antiseptics and astringents in other conditions. Instillation of silver nitrate solution has been investigated for pleurodesis in the management of malignant effusions. Silver nitrate has been used in cosmetics to dye eyebrows and eye lashes.

Homoeopathy.

Silver nitrate has been used in homoeopathic medicines under the following names: Argent. Nit.; Argenti nitras; Argentum nitricum; Arg. nit.
1. van Hasselt P, Gudde H. Randomized controlled trial on the treatment of otitis externa with one per cent silver nitrate gel. J Laryngol Otol 2004; 118: 93–6
2. Dalela D, et al. Silver nitrate sclerotherapy for ‘clinically significant’ chyluria: a prospective evaluation of duration of therapy. Urol Int 2004; 72: 335–40
3. da Silveira Paschoalini M, et al. Prospective randomized trial of silver nitrate vs talc slurry in pleurodesis for symptomatic malignant pleural effusions. Chest 2005; 128: 684–9
4. Alidaee MR, et al. Silver nitrate cautery in aphthous stomatitis: a randomized controlled trial. Br J Dermatol 2005; 153: 521–5.

💊 Preparations

BP 2008: Sterile Silver Nitrate Solution; USP 31: Silver Nitrate Ophthalmic Solution; Toughened Silver Nitrate.

Proprietary Preparations

Denm.: Helvedstensstifter†; Lapis; Ger.: Mova Nitrat; Pol.: Mova Nitrat; Port.: Argenpal†; Spain: Argenpal. Multi-ingredient: Austral.: Super Banish†; Spain: Argentofenol†; UK: Avoca.
Published May 08, 2019.