What role do laxatives play in the management of constipation in adults, and what are the potential side effects?

Role of laxatives in the management of constipation in adults: Laxatives are used when lifestyle measures such as increasing dietary fibre, fluid intake, and physical activity have not sufficiently relieved constipation symptoms. They help by softening stools, increasing stool frequency, or stimulating bowel motility depending on the type of laxative used. Initial treatment usually starts with bulk-forming laxatives like ispaghula, which require adequate fluid intake to be effective. If stools remain hard or difficult to pass, osmotic laxatives such as macrogol are added or substituted. Lactulose is considered second-line if macrogol is ineffective or not tolerated. When stools are soft but difficult to pass or there is a sensation of incomplete evacuation, stimulant laxatives may be added. In opioid-induced constipation, bulk-forming laxatives are not recommended; instead, osmotic and stimulant laxatives are preferred. For chronic cases unresponsive to at least two laxatives from different classes at maximum tolerated doses for six months, prokinetic agents like prucalopride may be considered. The goal is to titrate laxatives to produce soft, formed stools without straining at least three times per week, with regular review and dose adjustment as needed.

Potential side effects of laxatives: Osmotic laxatives (e.g., lactulose, sorbitol) may cause abdominal colic, gas, and abdominal distension. Stimulant laxatives can cause abdominal cramping and discomfort. Oral laxatives may lead to loose stools and prolonged bowel activity. Bulk-forming laxatives require adequate fluid intake to avoid worsening constipation or causing bowel obstruction. Overuse or inappropriate use of laxatives can lead to dependency or electrolyte imbalances, although this is less common with appropriate use. Patients should be advised to gradually reduce and stop laxatives once normal bowel habits are restored.

Overall, laxatives are an important part of a stepped approach to managing constipation in adults, tailored to symptom type and severity, with attention to side effects and patient preference.

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