Laxative

Definition

Laxatives are medications used to treat and prevent constipation by stimulating bowel movements. Different classes work by various mechanisms.

Classes

• Bulk-forming (psyllium, methylcellulose): First-line; needs adequate fluids; 1 to 3 days to work.
• Stool softeners (docusate): Prevent straining; no laxative effect alone.
• Osmotic (polyethylene glycol, lactulose, magnesium hydroxide): Draw water into bowel.
• Stimulant (senna, bisacodyl): Increase peristalsis; avoid long-term use.
• Lubricant (mineral oil): Soften stool; aspiration risk.
• Saline (Fleet enema): Quick, osmotic.

Nursing Considerations

• Bulk-forming: encourage hydration or risk impaction
• Assess for abuse. Chronic use causes electrolyte imbalance (especially hypokalemia)
• Avoid in suspected bowel obstruction
• Lactulose for hepatic encephalopathy (goal 2 to 3 soft stools/day)

NCLEX Relevance

Lactulose for ammonia reduction. Fiber and fluids first-line.