Place In Therapy
LACTULOSE
Lactulose, an osmotic laxative, is
a synthetic disaccharide that is not absorbed by the small intestine but is
readily metabolized by colonic bacteria. A review of the current literature
presented considerable amount of evidence to support the use of lactulose in the
management of chronic constipation. The main systematic review examining the
efficacy and safety of traditional medical therapies for constipation concluded
that there is currently Level II, Grade B evidence to support the use of
lactulose in chronic constipation1. A review of the studies
demonstrated an improvement in stool frequency and stool consistency with
lactulose in chronic constipation. Furthermore, several primary literatures have
demonstrated the lactulose is significantly better than placebo in promoting
defecation in chronic constipation5. Based on the literature review,
lactulose may have a beneficial role in patients unresponsive to first-line
therapy that include patient education, lifestyle and diet modification, fibre
supplementation and/or bulk-forming laxatives. It must be noted that although
increasing fibre intake is frequently suggested as the first-line treatment, a
fair proportion of patients with chronic constipation will not be helped by
fibre. In such case, osmotic laxatives can be considered as the treatment of
choice. In fact, one primary literature has demonstrated that lactulose may have
better efficacy than fibre for chronic constipation4. When compared
to senna-fibre combination, it was observed that both had similar tolerability,
however, senna-fibre combination was more effective in stool frequency and
consistency while being less expensive3. Among the osmotic laxatives, it was noted
that PEG is better than lactulose in outcomes of stool frequency per week, form
of stool, relief of abdominal pain and the need for additional
products2. As such, it is recommended that PEG be used in preference
to lactulose in chronic constipation. In terms of safety of lactulose use, the
literature indicates that it is well-tolerated with no major adverse effects
compared to other treatment options. The most common side-effects are bloating,
flatulence and cramping. Lactulose is not recommended in patients with
gastrointestinal abnormalities and those who require a galactose-free
diet6. However, it can be used
in diabetic patients. In terms of special populations such as infants, children
and adults, there is currently a lack of studies in such population, however,
tertiary literature suggest its safe use in children and adults.
References
1. Ramkumar D, Rao SC. Efficacy and safety of traditional medical therapies for chronic constipation: systematic review. Am J Gastroenterol 2005;100:936-971.
2. Lee-Robichaud H, Thomas K, Morgan J, Nelson RL. Lactulose versus polyethylene glycol for chronic constipation. Cochrane Database Syst Rev 2010;(7):CD007570.
3. Passmore AP, Wilson-Davies K, Stoker C, Scott ME. Chronic constipation in long stay elderly patients: a comparison of lactulose and a senna-fibre combination. British Medical Journal 1993:307(6907):769-771.
4. Quah HM, Ooi BS, Seow-Choen, Sng KK, Ho KS. Prospective randomized crossover trial comparing fibre with lactulose in the treatment of idiopathic chronic constipation. Tech Coloproctol 2006,10:111-114.
5. Casparis AW, Braadbaart SGE, Bergh-Bohlken, Mimica M. Treatment of chronic constipation with lactulose syrup: results of a double-blind study. Gut 1978,9,84-86.
6. Canadian Pharmacist Association. Patient Self Care, 2010. Chapter 31: Constipation. Page 262-80.
References
1. Ramkumar D, Rao SC. Efficacy and safety of traditional medical therapies for chronic constipation: systematic review. Am J Gastroenterol 2005;100:936-971.
2. Lee-Robichaud H, Thomas K, Morgan J, Nelson RL. Lactulose versus polyethylene glycol for chronic constipation. Cochrane Database Syst Rev 2010;(7):CD007570.
3. Passmore AP, Wilson-Davies K, Stoker C, Scott ME. Chronic constipation in long stay elderly patients: a comparison of lactulose and a senna-fibre combination. British Medical Journal 1993:307(6907):769-771.
4. Quah HM, Ooi BS, Seow-Choen, Sng KK, Ho KS. Prospective randomized crossover trial comparing fibre with lactulose in the treatment of idiopathic chronic constipation. Tech Coloproctol 2006,10:111-114.
5. Casparis AW, Braadbaart SGE, Bergh-Bohlken, Mimica M. Treatment of chronic constipation with lactulose syrup: results of a double-blind study. Gut 1978,9,84-86.
6. Canadian Pharmacist Association. Patient Self Care, 2010. Chapter 31: Constipation. Page 262-80.