Sodium Arothiomalate (gold)

Question 1

What class of drugs does sodium aurothiomalate belong to?

Answer 1

Antirheumatic agents

Question 2

What are examples of other drugs in this calss/

Answer 2

D-penicillamine

Question 3

What is Sodium aurothiomalate indicated for?

Answer 3

Management of active progressive rheumatoid arthritis

Progressive juvenile chronic arthritis (esp. polyarticular or seropositive)

Question 4

What is the dose of Sodium aurothiomalate for rheumatoid arthritis?

Answer 4

test dose of 10mg, followed by weekly doses of 50mg until there is evidence of remission.
Then gradually increase dose interval to 4 weeks.

Benefit not seen until 300-500mg given (~9-10 weeks)

Discontinued if no remission after 1g has been given

via deep IM injection

Question 5

What is the mechanism of action of Sodium aurothiomalate?

Answer 5

Penetrates into joint cavity and affects lysosomal membranes
Binds to plasma proteins including IgG, the rheumatoid factor and the immune complex. When lysosomes ingest this complex, the gold is absrobed and inactivates lysosomal enzymes within the cell.

Also
Impairs T cell activation
inhibits TNF alpha, IL-1, IL-12

Question 6

What is the role of Sodium aurothiomalate in therapy?

Answer 6

Similar in efficacy to D-Penicillamine, MTX and SLZ, but not as well tolerated as MTX and SLZ

Used less frequently due to toxicity, lack of long term benefits etc.

Question 7

What is the characteristic pharmacokinetic and pharmacodynamic paramerts of sodium aurothiomalate?

Answer 7

Highly protein bound, mainly to albumin
half life (in synovial fluid): 6-7 days
Significant excretion in urine and faeces.

Question 8

What are the precautions associated with sodium aurothiomalate use?

Answer 8

elderly, history of urticaria, eczema, colitis, patients with blood disorder, GI bleeds, aspirin induced hepatic dysfunction, marked hypertension, compromised cerebral and/or CV circulation or unexplained proteinuria repeatedly above 300mg/L

Pregnancy class B: avoid, limited data, not necessary to withdraw if condition is well controlled (consider reducing dose and frequency instead)
Avoid in breastfeeding

Question 9

What are the contraindications of sodium aurothiomalate use?

Answer 9

severe renal/hepatic disease, diabetes, gold-induced disorders including necrotising entercolitis, pulmonary fibrosis, exfoliative dermatitis, bone marrow aplasia, history of bone marrow toxicity, blood dyscrasias, severe skin conditions, lupus, acute porphyria

Question 10

what are some adverse reactions associated with sodium aurothiomalate use?

Answer 10

severe anaphylactic reactions, nausea, vomiting, stomatitis, taste disturbances, colitis, hepatotoxicity with cholestatic jaundice

pulmonary fibrosis, peripheral neropathy, mouth ulcers, proteinuria, haematuria, blood disorders, nephrotic syndrome, gold deposits in the eye, alopecia, skin reactions, irreversible pigmentation in sun exposed areas.

Question 11

What are some drug interactions associated with sodium aurothiomalate use?

Answer 11

Flushing and hypotension with ACE inhibitors

Increased risk of toxicity with penicillamine

Question 12

What are the alarm bells associated with sodium aurothiomalate use?

Answer 12

Urine tests, FBC must be performed before starting treatment and before each IM injection

Rashes with pruritus often occur after 2-6 months of treatment. Discontinuation may be necessary.

Patients to seek prompt medical condition if diarrhoea, sore throat, fever, infection, non-specific illness, unexplained bleeding and bruising, purpura, mouth ulcers, metallic taste, rash, breathlessness, or cough develops