Silver nitrate use and toxicity

last modified on: Tue, 03/06/2018 - 13:42

Silver Nitrate Toxicity
 
The use of silver nitrate and when it is considered a poison.
 return to: Common Call Problems Epistaxis; Lip biopsy; Panendoscopy

  1. Response from Pharmacy Information Service at UIHC re: possible toxicity
    1. Silver nitrate when used topically has been noted to cause irritation, redness.
    2. The main toxic effect of topical silver nitrate is a generalized gray pigmentation of the skin called argyria. This is very rare with chronic topical use and typically occurs more frequently with chronic systemic absorption. On average, 3.8 grams of silver nitrate given orally can cause argyria to begin to be observed.
    3. Silver nitrate is mainly considered a poison with ingestion due to the corrosive nature of the compound. If ingested, silver nitrate can cause potentially fatal gastroenteritis and gastrointestinal bleed. In toxicity studies, 29mg/kg administered to humans via an unknown route caused no fatalities, however 50mg/kg given orally to mice was lethal to 50% of the subjects.
      Stephanie Malenfant, PharmD MPH
      PGY1 Pharmacy Practice Resident
      University of Iowa Hospitals and Clinics
  2. More infomration re: Silver Nitrate from package insert for ARZOL® (silver nitrate applicators) = Silver Nitrate 75% and Potassium Nitrate 25%) Arzol Cehmical Co. Keene, NH 03431 issued May 2002
    1. Silver nitrate is a powerful chemical germicide and, on contact with living tissue, escharotic.
      1. "Toughened silver nitrate" and "Lunar caustic" are terms to describe the combination of silver nitrate with potassium nitrate
      2. Exposure to light causes the silver in the tip to turn brown, but does not affect its therapeutic action
      3. Moisture has a deteriorating effect on the tip (can make it break or loosen from the applicator)
      4. Improper use of silver nitrate can cause chemical burns (it is a caustic compound)
        1. Use in neonates (as on the umbilicus) should be of short duration
        2. Do not use in the eyes
    2. Indications:
      1. Skin
        1. Cauterization of wounds and sluggish ulcers
        2. Removal of granulation tissue and warts
      2. Mucous membranes
        1. Oral ulcers and apthae
        2. Control of epistaxis by direct application to hemorrhagic site