What is a potential side effect of Irinotecan and Topotecan?

Irinotecan and Topotecan are both chemotherapy medications commonly used in the treatment of certain cancers. A significant and potentially life-threatening side effect of these drugs is severe diarrhea, which can occur due to the drugs' effect on the gastrointestinal tract. This condition stems from the inhibition of DNA topoisomerase I, an enzyme critical for DNA replication and repair. When this enzyme is blocked, cell death can occur in rapidly dividing cells, such as those in the intestinal lining. The result is a disruption in normal gut flora and function, leading to excessive watery stools.

This side effect requires careful monitoring and management because it can lead to dehydration and electrolyte imbalances, which can be dangerous if not treated promptly. While nausea, liver damage, and hair loss can occur with various chemotherapy agents, they are not as specifically associated with the use of Irinotecan and Topotecan as life-threatening diarrhea is. This distinction highlights the importance of understanding the specific risks associated with different chemotherapeutic agents for effective patient management.