What is a potential risk associated with long-term use of metoclopramide?

Long-term use of metoclopramide is associated with an increased risk of tardive dyskinesia, a serious and often irreversible movement disorder characterized by repetitive, involuntary movements, particularly of the face and tongue. Metoclopramide acts as a dopamine receptor antagonist, and prolonged blockade of dopamine receptors in the brain can lead to the development of this condition. This risk is particularly heightened in older adults and those who are on high doses or use the medication for extended periods.

In contrast, the other options, while they may pertain to general concerns in pharmacology, do not specifically relate to the established risk profile of metoclopramide. For instance, allergic reactions can occur with many medications but are not predominantly linked to metoclopramide’s long-term use. Liver damage and gastrointestinal bleeding are more associated with different classes of medications or specific contexts rather than metoclopramide itself. Therefore, the focus on tardive dyskinesia is critical for understanding the safety profile and monitoring needs of patients on this medication over time.