Overview of pharmacological treatment for depressive disorders

Pharmacological treatment is a fundamental tool in the approach to depressive disorders, especially in cases of moderate to severe intensity.

Depression manifests itself through affective symptoms (sadness, anhedonia), cognitive symptoms (hopelessness, suicidal thoughts), behavioral symptoms (isolation, inactivity), and somatic symptoms (sleep, appetite, and energy disturbances), which significantly compromise the patient's quality of life.

Classification of severity and initial approach

The severity of a depressive episode is determined by the number and intensity of symptoms.

• Mild: 4-5 symptoms.

• Moderate: 6-7 symptoms.

• Severe: 8 or more symptoms.

In mild cases, treatment may focus on psychotherapy and self-care measures. From moderate levels onwards, pharmacological intervention is indicated.

First-line drugs

The most commonly used group are selective serotonin reuptake inhibitors (SSRIs), such as:

• Sertraline

• Fluoxetine

• Paroxetine

Other groups are also used:

• Dual reuptake inhibitors: venlafaxine, duloxetine

• Other antidepressants: mirtazapine, amitriptyline

The choice depends on the patient's profile, their predominant symptoms, and their tolerance to side effects.

Phases of antidepressant treatment

Treatment should consist of three phases:

• Acute phase: initial symptom relief (6 to 12 weeks).

• Continuation phase: preventing relapse (4 to 9 months).

• Maintenance phase: preventing recurrence (1 year or more, in recurrent cases).

Resistant depression and augmentation strategies

Depression is considered resistant when the patient does not improve after two complete courses of antidepressant treatment. In these cases, augmentation strategies are used, including:

• Combination of antidepressants

• Use of atypical antipsychotics: aripiprazol, quetiapina, olanzapina

• Mood stabilizers such as lithium

• Thyroid hormone and psychostimulants in selected cases

Neuromodulation in severe depression

When drug treatments are not effective, neuromodulation therapies are used, such as:

• Electroconvulsive therapy (ECT): effective in severe depression with psychotic symptoms

• Transcranial magnetic stimulation: a non-invasive alternative, useful in refractory patients

• Ketamine infusion: fast-acting in severe cases with sui