Products
Silver is used as an active pharmaceutical ingredient in creams (e.g., as silver sulfadiazine) and wound dressings, among other products. Some medical devices are also coated with silver.
Structure and properties
Silver (Ag, Mr = 107.9 g/mol) is a chemical element that exists as a soft, malleable, white, and lustrous transition and noble metal with a high melting point of 961 °C. It is characterized by its very good electrical and thermal conductivity. Among other things, silver is soluble in concentrated nitric acid, forming silver nitrate (AgNO3) is formed. Objects made of silver, such as silverware, form silver nitrate with the hydrogen sulfide present in the air (H2S) over time to form the black silver sulfide (Ag2S), whereby they “tarnish.” Discolored silver can be cleaned, for example, with chemicals or with aluminum foil and common salt. They are not oxides because silver has a low affinity for oxygen. The silver salt silver nitrate is very easily soluble in water. Sodium chloride solutions can be used to neutralize silver nitrate because the white silver chloride (AgCl) dissolves poorly in water. This precipitation is also used to detect silver ions.
- AgNO3 (silver nitrate) + NaCl (sodium chloride) AgCl ↓ (silver chloride) + NaNO3 (sodium nitrate)
Due to the above properties, pure silver is not suitable for jewelry manufacturing. Therefore, alloys with other metals are used, such as copper: sterling silver is harder than silver and slightly reddish.
Effects
Silver has antiseptic (antibacterial, antifungal) and protein precipitating properties.
Indications
- Silver is used in medicine mainly as a disinfectant for the skin and as such is contained, for example, in creams and wound dressings.
- For the sterilization of drinking water.
- As a reagent.
- In the form of the silver nitrate sticks for cauterization , such as warts or ulcers.
- Against body odors, for example in textiles.
Dosage
According to the professional information. The creams are usually applied once a day.
Contraindications
Contraindications include (selection):
- Hypersensitivity
- Oral administration
Full precautions can be found in the drug label.
Adverse effects
Possible adverse effects include local skin reactions. Silver may cause gray discoloration of the skin when exposed to sunlight. Therefore, a bandage should always be applied and clothing worn after application! It is strongly advised against taking colloidal silver because of the undesirable effects. Among other things, the silver can be deposited in the skin, mucous membrane and other organs such as the kidneys and eyes. This can lead to an often irreversible (irreversible) blue to gray discoloration of the skin and mucous membranes as well as visual disturbances (argyrie). Other side effects are described in the literature.
Cf.
- Silver nitrate
- Silver nitrate sticks
- Colloidal silver
