Which laxative is linked to potassium loss in patients taking diuretics?

Which laxative is linked to potassium loss in patients taking diuretics?

• A. Bisacodyl
• B. Methylcellulose
• C. Senna
• D. Docusate sodium

Answer: (C)

Potassium loss with laxatives occurs most with stimulant laxatives, which increase colon motility and promote secretion of water and electrolytes into the bowel. Senna is a classic stimulant laxative that accelerates intestinal transit and enhances electrolyte and fluid loss in the gut. In patients taking diuretics, which already promote potassium wasting by the kidneys, adding a laxative that also depletes potassium markedly increases the risk of hypokalemia, with symptoms like weakness, cramps, and potential heart rhythm issues. Therefore, senna is the best answer because its mechanism directly ties to potassium decline in the context of diuretic use. Bulk-forming laxatives (methylcellulose) and stool softeners (docusate sodium) do not cause significant potassium loss, so they don’t carry the same electrolyte-depletion risk. While stimulant laxatives can all affect electrolytes, senna is the most classic association in this specific scenario.

Potassium loss with laxatives occurs most with stimulant laxatives, which increase colon motility and promote secretion of water and electrolytes into the bowel. Senna is a classic stimulant laxative that accelerates intestinal transit and enhances electrolyte and fluid loss in the gut. In patients taking diuretics, which already promote potassium wasting by the kidneys, adding a laxative that also depletes potassium markedly increases the risk of hypokalemia, with symptoms like weakness, cramps, and potential heart rhythm issues. Therefore, senna is the best answer because its mechanism directly ties to potassium decline in the context of diuretic use.

Bulk-forming laxatives (methylcellulose) and stool softeners (docusate sodium) do not cause significant potassium loss, so they don’t carry the same electrolyte-depletion risk. While stimulant laxatives can all affect electrolytes, senna is the most classic association in this specific scenario.