Which of the following is NOT a common side effect of local anesthetics?

Local anesthetics can produce a range of side effects, primarily due to their action on nerve tissue and the potential for systemic absorption. Common side effects include cardiac arrhythmias, which may occur due to toxicity affecting the cardiac conduction system. Seizures can also happen as a result of central nervous system toxicity when local anesthetics reach high plasma concentrations. Nausea is frequently reported and can occur for various reasons, including the body's response to the anesthetic or anxiety related to the procedure.

In contrast, hair loss is not a recognized common side effect associated with local anesthetics. While hair loss can be influenced by a variety of factors, including medications and medical conditions, it is not linked specifically to the use of local anesthetics. Therefore, identifying hair loss as an uncommon side effect highlights its disconnect from the well-documented effects of local anesthetics and helps clarify the understanding of their side effect profiles.