Colchicine

Introduction:

It is an alkaloid obtained from plant, Colchicum autumnale. It has been found effective in the treatment of acute gout.

Mechanism of action:
It causes the disruption of cellular activities such as movement of granulocytes to the affected area and phagocytosis. It also inhibits the synthesis and release of leukotriene B4.

Action:

It relieves pain. Though it cannot prevent the progression of gout to acute gouty attacks but it is used as a prophylactic drug in this case so helps to keep down pain and frequency of acute attacks. It is now used in combination with probenecid.

Indomethacin is now replacing Colchicine.

Therapeutic Uses:
It is used for the relief of pain and inflammation in acute gout within 12-24 hours.

Pharmacokinetics:
It is absorbed rapidly from GI tract. Its peak plasma level is attained within 2 hours. Its plasma half life is 9 hours. It is recycled in the bile and excreted unchanged in the feces or urine.

Dosage:
The usual dosage of colchicines is 0.6 mg one to three times daily as a prophylaxis of gout.

Adverse effects:
It may cause nausea, vomiting, abdominal pain and diarrhea.
Prolonged administration may cause myopathy, aplastic anemia and alopecia.

Contraindications:
It is contraindicated in pregnancy.

Precautions:
It should be used with caution in hepatic, renal or cardiovascular diseases.