Background/aims: Chronic constipation is a common clinical problem that frequently does not respond to routine therapeutic measures. Colchicine may be effective in this condition because it is known to stimulate intestinal motility and commonly causes diarrhea in patients taking the drug for either gouty arthritis or familial mediterranean fever. Methods: We evaluated 59 patients with constipation and found organic pathology in four (6.7%) of them. The other 55 (93.2%) patients were diagnosed as functional constipation according to Rome-2 criteria and were prescribed laxatives. Thirteen (23.6%) of these 55 patients with functional constipation were resistant to medical therapy and were studied prospectively. There were eight males and five females with a mean age of 42.4 ± 6.7 years. They were treated with oral colchicine 0.5 mg three times a day for 12 weeks. Results: During the study, the mean number of spontaneous bowel movements was 1.1 ± 0.6 per week initially, 1.6 ± 0.8 during routine treatment of constipation with laxatives and enemas and 5.8 ± 1.1 per week with colchicine treatment (p<0.05). Symptoms of abdominal pain, nausea and bloating improved significantly during colchicine treatment. Conclusions: Oral colchicine (0.5 mg three times a day) therapy appears to be a promising treatment for chronic functional constipation.