Lithium carbonate is commonly prescribed for which type of disorder?

Lithium carbonate is primarily used in the treatment of bipolar (manic-depressive) disorder, which is characterized by extreme mood swings that include episodes of mania and depression. Lithium acts as a mood stabilizer, helping to reduce both the intensity and frequency of these mood fluctuations, making it a cornerstone of management for individuals diagnosed with this disorder. Its effectiveness in stabilizing mood has been well-documented in clinical research, leading to its widespread acceptance in psychiatric treatment protocols for bipolar disorder.

The other options, while indicative of various mental health conditions, are not primary indications for lithium therapy. Anxiety disorders typically require different classes of medications, such as SSRIs or benzodiazepines. Schizophrenia is often managed with antipsychotics rather than mood stabilizers. Depressive disorders may involve mood stabilizers in some complex cases, but lithium is not first-line treatment for typical depressive presentations. Thus, the specificity and proven effectiveness of lithium in treating bipolar disorder clearly establishes it as the correct answer in this context.