Penicillamine therapy

Penicillamine or Distamine is indicated for the treatment of active R.A. and some other inflammatory arthropathies. It is normally used together with NSAIDs particularly in the early stages of treatment. Response to treatment cannot be expected before three months and may not occur until after six months of treatment.

CONTRA-INDICATIONS

Pregnancy and lactation
Gross renal, lung, bowel or hepatic disease
Blood dyscrasias
Known hypersensitivity (not to penicillin)

DOSAGE

Starting Dose 125mg daily
Dose increments 125mg monthly until dose of 500mg daily or clinical response achieved.
If inadequate response dose can be increased to 750mg daily or higher.
Higher doses should only be used after consultation.
Stop drug if treatment continued for six months without positive response.
Total duration of treatment - as long as indicated by clinical condition.
Take before food, Do not take oral iron concomitantly

MONITORING

Pre-treatment screening
monitoring monthly.

PRE TREATMENT SCREENING	EACH MONITORING VISIT
Haemoglobin Total white cell count Neutrophil count Platelet count Urinalysis for protein and blood Biochemical Profile	Haemoglobin Total white cell count Neutrophil count Platelet count Urinalysis for protein and blood

ADVERSE EVENTS

LABORATORY EVENTS	VALUES	ACTION
Leucopaenia	< 3.5 x 10 ⁹ /l	STOP + seek advice
Neutropaenia	< 2.5 x 10 ⁹ /l	STOP + seek advice
Thrombocytopaenia	< 150 x 10 ⁹ /l	STOP + seek advice
Sequential falls in WBC or neutrophils	> 10% on 3 occasions	STOP + seek advice
Sequential falls in Platelets	> 10% on 3 occasions	STOP unless falls are from high level e.g. 600, 500, 400 x 10 ³ which are response to treatment
Haematuria	trace or +	Continue Drug
Haematuria	++ or +++	STOP Drug Check MSU Consider other causes Seek advice
Proteinuria	trace or +	Continue Drug
Proteinuria	++ or +++	STOP Drug Check MSU 24 hour urinary protein Seek Advice

CLINICAL ADVERSE EVENTS	MANAGEMENT
Rash	Often non-specific erythematous, dry and itchy. STOP drug if severe Consider using 1% hydrocortisone and/or anti-histamines.
Metallic taste	Common in early weeks.STOP if severe. Settles with time. Stop if unacceptable.
Nausea	Reduce dose Take with food. STOP if unacceptable
Lupus syndrome	Rare and difficult to diagnose. Stop if unacceptable
Dyspnoea/bronchiolitis	STOP drug and Seek advice
Myaesthenic symptoms	STOP drug and Seek advice

Source: Dr PR Crook, Consultant Rheumatologist.