COLCHICINA Ref.[4345] Active ingredients: Colchicine

Adults only:

Gout: 1mg initially, followed by 500 micrograms every two to three hours until relief of pain is obtained or vomiting or diarrhoea occurs. A total dose of 6mg should not be exceeded. The course should not be repeated within three days.

Renal Impairment: For mild/moderate renal impairment (creatinine clearance 10-50 ml/minute), reduce dose or increase interval between doses (see section 4.3 Contraindications).

For use with allopurinol or uricosuric drugs: 500 micrograms two to three times daily.

Elderly: To be given with great care.

Children: Not recommended.

Colchicine has a narrow therapeutic window and is extremely toxic in overdose. Patients at particular risk of toxicity are those with renal or hepatic impairment, gastrointestinal or cardiac disease, and patients at extremes of age.

Colchicine overdose is complex and specialist advice should be promptly obtained. There is often a delay of up to 6 hours before toxicity is apparent, and some features of toxicity may be delayed by 1 week or longer. All patients, even in the absence of early symptoms, should be referred for immediate medical assessment.

a) Symptoms

Early features (up to 1 day after ingestion) include a feeling of burning and rawness in the mouth and throat, difficulty in swallowing, nausea, vomiting, abdominal pain and diarrhoea. Diarrhoea may be profuse, bloody and accompanied by tenesmus, and the patient may present with electrolyte disturbances and hypovolaemic shock. These symptoms, coupled with vascular damage, may lead to dehydration, hypotension and shock.

Features after 1 to 7 days include confusion, decreased cardiac output, cardiac arrhythmias, renal and hepatic impairment, respiratory distress, hyperpyrexia and bone marrow depression. This can progress in severe cases to multiple organ failure with accompanying bone marrow aplasia, CNS toxicity, convulsions, coma, hepatocellular damage, rhabdomyolysis, respiratory distress, myocardial injury, renal damage and disseminated intravascular coagulation.

Death may be due to respiratory depression, cardiovascular collapse or sepsis.

In surviving patients, alopecia, rebound leucocytosis and stomatitis may occur about 10 days after the acute overdose.

b) Treatment

Consider oral activated charcoal in adults who have ingested more than 0.1 mg/kg bodyweight within 1 hour of presentation, and in children who have ingested any amount within 1 hour. Further doses of activated charcoal may enhance systemic elimination and may be considered in patients who have ingested more than 0.3 mg/kg
Haemodialysis and haemoperfusion do not enhance Colchicine elimination.

Management should include general symptomatic and supportive measures as indicated by the patient’s clinical condition, including monitoring of vital signs, ECG, haematological and biochemical indices. Respiration may need assistance. Circulation should be maintained and fluid and electrolyte imbalance corrected.

Morphine sulphate 10mg, intramuscularly, may be given to relieve severe abdominal cramps.

To allow for the delayed onset of symptoms, patients should be carefully monitored for at least 6 hours after ingestion, or for 12 hours if they have taken more than 0.3 mg/kg. After this time, asymptomatic patients may be discharged with advice to return if gastrointestinal symptoms appear.

Three years in polypropylene or polyethylene tablet containers.

Two years in strip packs of opaque white or clear PVC film and 20µ aluminium foil of 10 or 14 tablets.

Do not store above 25°C.

Store in the original container.

Polypropylene or polyethylene containers containing 100 or 500 tablets. Strip packs of opaque white or clear PVC film and 20µ aluminium foil of 10 or 14 tablets.

The tablets will be packed in multiple strips of 10 tablets ie 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100 tablets.

The tablets will be packed in multiple strips of 14 tablets ie 14, 28, 56, 84 or 112 tablets.

None.