Products
Gold compounds are commercially available (worldwide) in the form of capsules and injection solutions (e.g., Ridaura, Tauredon), among others. They are rarely used medicinally today.
Structure and properties
Elemental gold (Latin: aurum, abbreviation: Au, M.
r
= 96.97 g/mol, atomic number 79) is a chemical element and a lustrous noble metal with a yellow color that belongs to the transition metals. It has a high density of 19.3 g/cm
3
and a high melting point of 1063 °C. As a pure material, it is relatively soft and ductile, making it very easy to machine. Because it is so soft, it is often used in the form of alloys together with other metals, for example with copper, nickel or silver. Gold is formed in dying stars (supernovae). Gold is well suited for making jewelry, coins, and art because it is unreactive, does not tarnish, does not oxidize when exposed to air, and is resistant to most environmental conditions. It is characterized by its high chemical and thermal stability and good electrical conductivity. However, gold can certainly be dissolved and ionized, for example with a mixture of concentrated hydrochloric acid and concentrated nitric acid, the so-called aqua regia. It forms mainly monovalent and trivalent compounds. In nitric acid alone and most other acids and bases, however, it is insoluble. Gold is widely distributed and often occurs in company with quartz and pyrite. It is found in large quantities, but in low concentrations also in seawater. Switzerland also has natural gold deposits. Gold is contained in medicines in the form of so-called gold compounds. These are complexes with soft ligands, especially with sulfur. The active ingredients include:
- Sodium aurothiomalate (Tauredon).
- Auranofin (Ridaura)
- Aurothioglucose
- Aurotioprol
- Sodium aurotiosulfate
Effects
Gold compounds (ATC M01CB) have immunosuppressive, anti-inflammatory, and antimicrobial (antibacterial) properties. Gold has a very long half-life of about 250 days (sodium aurothiomalate) or 80 days (auranofin). Patients continue to excrete small amounts for years after therapy. The effects are not immediate, but occur after three to six months.
Indications for use
For the basic therapy of rheumatic diseases:
- Rheumatoid arthritis
- Chronic polyarthritis
- Psoriatic arthritis
Dosage
According to the SmPC. Sodium aurothiomalate is injected intramuscularly (deep intragluteal). Auranofin may be administered perorally.
Contraindications
For complete precautions, see the drug label.
Adverse effects
Gold can cause numerous side effects. The most common possible adverse effects include:
- Gastrointestinal disturbances, taste disturbances.
- Mucosal inflammation, e.g., an inflammation of the oral mucosa, inflammation of the tongue.
- Disorders of the hematopoietic system: thrombocytopenia, granulocytopenia, anemia.
- Skin reactions, hair loss, gold deposits in the skin.
- Proteinuria, hematuria
- Liver disease
