When initiating quetiapine, which blood test should be monitored?

Monitoring prolactin levels when initiating quetiapine is crucial because this antipsychotic medication can influence hormone levels, particularly prolactin, due to its antagonistic effects on dopamine receptors. An elevation in prolactin can lead to various side effects, including galactorrhea, amenorrhea, and sexual dysfunction. Therefore, regularly checking prolactin levels helps assess any potential hormonal imbalances that could arise from treatment with quetiapine, enabling timely intervention when necessary.

While the other tests listed may be relevant in specific circumstances, they are not as directly associated with quetiapine's primary pharmacological effects as prolactin monitoring is. For instance, complete blood counts and liver function tests can be important in monitoring overall health and side effects of many medications, but are less specific to the action of quetiapine. Cholesterol levels are more associated with the metabolic effects of various antipsychotics but are not directly influenced by the initiation of quetiapine therapy. Therefore, prolactin levels are the primary tests recommended for monitoring when starting treatment with quetiapine.