Which laxative ingredient was removed from the market due to concerns about cardiac toxicity?

• A. Bisacodyl
• B. Phenolphthalein
• C. Docusate
• D. Senna

Answer: (B)

Phenolphthalein was withdrawn because safety signals suggested it could affect the heart in some people. When laxatives containing phenolphthalein were used, especially in frequent or high doses, they could lead to dehydration and electrolyte imbalances. These changes can place extra stress on the heart and, in susceptible individuals, trigger abnormal heart rhythms or other cardiac problems. To protect patients, regulators removed products with this ingredient from the market. Other laxatives like bisacodyl, docusate, and senna did not show the same level of cardiac risk at the time of review, so they remained available.