Gold for therapeutic purposes

Introduction

Gold compounds are primarily used in the treatment of rheumatoid arthritis. However, they may be useful in the treatment of some skin diseases, including pemphigus vulgaris, epidermolysis bullosa acquisita, and severe or resistant cutaneous lupus erythematosus.

Another name for gold tablets administered orally is auranofin. The trade name in New Zealand is Ridaura®. Gold injection, known as sodium aurothiomalate, is also available.

How to use gold compounds

Gold compounds should only be used by a doctor experienced in its use, as the risk of toxicity is high and side effects potentially dangerous. It is essential that treatment with the drug is not more disabling then the disease it is being used to treat.

Prior to starting treatment with gold compounds a routine baseline assessment should include:

• complete blood cell count
• renal function tests
• liver function tests

Regular monitoring of these should continue throughout treatment.

Similar doses to those used for treating rheumatoid arthritis are given. If there is no improvement by the time the total dose reaches 1g treatment should be stopped.

Contraindications to gold

Gold compounds should not be used under the following circumstances:

• Progressive renal disease
• Severe active hepatic disease
• History of hypersensitivity to gold compounds

Precautions when prescribing gold

Before starting treatment with gold compounds, the following should be considered:

• Allergies to any medicines, particularly any unusual or allergic reaction to gold or other metals
• Pregnancy
• Breast-feeding
• Other medical problems including:
  • blood or blood vessel disease
  • kidney disease
  • inflammatory bowel disease

Side effects of gold compounds

In addition to their helpful effects, gold compounds may also cause many side effects, some of which can be serious. These include:

• Skin rashes or itching: usually mild but in some instances may necessitate stopping treatment
• Ulcers, sores or white spots on lips or in mouth or throat
• Skin pigmentation due to prolonged treatment (chrysiasis)
• Loose stools or diarrhoea: usually mild and transient
• Stomach pain or cramps, bloated feeling, gas or indigestion
• Decrease or loss of appetite
• Nausea or vomiting
• Decrease in white blood count, possibly leading to blood disorders
• Transient abnormalities in liver and renal function tests
• Confusion and seizures

Drug interactions with gold compounds

There is very little specific information about interactions of gold compounds with other drugs. However, the potential for increasing gold toxicity is great, particularly when given with other drugs that have an effect on the renal, hepatic and blood systems. Such medicines include penicillamine, aminoglycosides, amphotericin B, penicillins, phenylbutazone, phenytoin, sulfonamides, nonsteroidal anti-inflammatories (NSAIDS), aciclovir and alcohol.