What is typically increased by Lithium use in terms of health monitoring?

Lithium is well-known for its role in the treatment of bipolar disorder, and one of the key aspects of monitoring patients on lithium therapy is assessing thyroid function. Lithium can affect thyroid hormones, often leading to an increased incidence of hypothyroidism. Regular monitoring of thyroid hormones such as TSH (thyroid-stimulating hormone) and T4 (thyroxine) is essential while a patient is on lithium to detect any potential disruptions in thyroid function early on.

Other choices do not reflect the typical effects of lithium use. For example, serum glucose levels are not directly impacted by lithium, blood pressure may fluctuate but is not universally increased, and while a complete blood count (CBC) may be monitored for general health or side effects, it does not show a typical increase as a direct consequence of lithium therapy. Hence, the correct answer reflects the specific need to monitor thyroid function due to lithium's potential effects on thyroid hormones.