For a patient presenting with symptoms of depression, which medication is considered the first-line treatment?

Escitalopram is considered a first-line treatment for a patient presenting with symptoms of depression due to its classification as a selective serotonin reuptake inhibitor (SSRI). SSRIs are widely recommended in clinical guidelines because they are effective in treating depression with a favorable safety profile. Escitalopram has been shown to improve mood and alleviate depressive symptoms by increasing the levels of serotonin, a neurotransmitter that is often lower in individuals with depression.

In addition to its efficacy, escitalopram is generally well-tolerated, which means that patients are less likely to experience severe side effects compared to many older antidepressants. This makes it a suitable choice for initial treatment, especially considering the importance of adherence to medication in managing chronic conditions like depression.

Other medications listed may be used in different cases or for specific purposes; for example, imipramine is a tricyclic antidepressant that is often not the first choice due to its side effects. Lithium is primarily used for bipolar disorder, while risperidone is an antipsychotic medication that may be used for certain mood disorders but is not typically the first-line treatment for unipolar depression.