What is a common side effect of 5-FU?

5-FU, or 5-fluorouracil, is a chemotherapeutic agent commonly used to treat various cancers, particularly colorectal cancer. One notable side effect associated with 5-FU treatment is hand-foot mouth syndrome, which is characterized by painful redness, swelling, and blistering of the palms of the hands and soles of the feet. This occurs due to the rapid turnover of epithelial cells, which is impacted by the cytotoxic effects of the drug.

The mechanism behind this side effect relates to the drug's action as an antimetabolite, disrupting normal cellular processes, particularly in rapidly dividing cells such as those in the skin. This highlights the importance of monitoring and managing side effects during cancer treatment, as they can significantly impact a patient's quality of life.

The other options represent side effects that may not be as specifically associated with 5-FU. For example, altered mental status is not a well-documented side effect of 5-FU, while pulmonary fibrosis is more commonly related to other chemotherapeutic agents. Bone marrow suppression does occur but is often less prominent compared to other drugs, making hand-foot mouth syndrome a more recognizable common side effect of 5-FU.