Which symptom is not typically associated with First Use Syndrome?

First Use Syndrome refers to a set of symptoms that can occur when a patient is first exposed to a particular substance, often seen in the context of treatment with medications or dialysis-related substances. This syndrome can manifest in various ways, affecting the cardiovascular, gastrointestinal, and nervous systems.

Nervousness, chest pain, and a funny taste in the mouth are symptoms that can be associated with First Use Syndrome. Nervousness might arise as a psychological response or anxiety related to the new experience of dialysis. Chest pain can occur due to the body's reaction to the sudden changes in fluid and electrolyte balance during the initial treatment. A funny taste in the mouth could stem from the contact of dialysis solutions with the body's systems and the new interaction with these substances.

However, an irregular heartbeat is not a common symptom associated with First Use Syndrome. While cardiac issues can occur in patients undergoing treatment due to underlying conditions or complications, irregular heartbeat is not a hallmark symptom of the initial exposure to the treatment and does not fall under the typical manifestations categorized as First Use Syndrome. This distinction highlights the multifaceted nature of the body's responses to new treatments and emphasizes the importance of recognizing and identifying specific symptoms accurately.