Colchicine is an alkaloid derived from crocuses that has anti-inflammatory properties. It is used as a treatment for gouty arthritis which results from a building up of uric acid in the joints. Because it is not a uricosuric, which increases the output of uric acid in urine, it is often combined with uricosurics to encourage the expelling of the uric acid from the joints.
Off label, it is used for other types of arthritis, leukaemia, multiple sclerosis and cirrhosis. It is absorbed from the intestinal tract and metabolised in the liver before being excreted in faeces.
It is contraindicated for patients with blood abnormalities and severe gastrointestinal, renal, hepatic or cardiac disease. Skin irritation may occur from intramuscular or subcutaneous injection. Common side effects include nausea, vomiting, diarrhoea and abdominal pain. Possibly life-threatening side effects are bone marrow depression, a severe drop in the number of white blood cells in the body (agranulocytosis) and aplastic anaemia.