Table 3 Laxative compounds commonly used to treat chronic constipationá…Ÿ
From: Chronic constipation in the elderly: a primer for the gastroenterologist
Type | Laxative agent | Mechanism of action | Possible side effects |
|---|---|---|---|
Bulking forming laxatives | Natural fibres (e.g., psyllium) | Intraluminal H2o binding, bulk forming and decrease stool consistency | Bloating, flatulence |
Semi-synthetic fibres (es. methylcellulose) | |||
synthetic fibres (e.g., Polyethylene glycol polycarbophil: Macrogol) | |||
Osmotic laxatives | Magnesium hydroxide, magnesium citrate, magnesium sulfate, sodium phosphate. | Interstitial H2o binding | hydroelectrolytic alterations |
Disaccharides and alditols | Lactulose, sorbitol. | Interstitial H2o binding | Bacterial fermentation with bloating and flatulence (low efficacy in slow transit constipation) |
Emollients laxatives | Paraffin oil, docusate sodium | Intraluminal H2o binding, bulk forming and decrease stool consistency | Discomfort, abdominal pain, cramping |
Stimulant laxatives | diphenylmethane derivatives (bisacodyl, sodium picosulfate) | Stimulating action on enteric nerves with decrease in peristaltic contractions. | Discomfort, abdominal pain, cramping |
Anthraquinones (senna, aloe, cascara) | Decrease in colic absorption of H2o and electrolytes |