Which potential effect of high levothyroxine sodium dosage should the nurse monitor for?

High dosages of levothyroxine sodium can lead to an excessive stimulation of the thyroid gland, causing an overabundance of thyroid hormone in the body. This can result in symptoms typically associated with hyperthyroidism, such as anxiety, tremors, restlessness, and increased heart rate. Monitoring for anxiety and tremors is crucial because these effects indicate that the dosage may be too high, potentially increasing the risk for more severe complications like heart palpitations or even arrhythmias.

In contrast, weight gain and dry skin are more commonly associated with insufficient thyroid hormone levels rather than an excess. Increased energy may seem like a positive effect; however, it is essential to consider that this can be misleading, as excessive energy and restlessness are signs of overstimulation rather than true vitality. Therefore, the most critical effects to monitor when a patient is on a high dose of levothyroxine include anxiety and tremors, as they are indicative of potential thyroid hormone toxicity.