psychiatric disorders
Medications for Treatment of Depression
Choice and Administration of Antidepressants
Choice of medication may be guided by past response to a specific antidepressant. Otherwise, selectiveserotoninreuptake inhibitors (SSRIs) are often the initial medications of choice. Although the different SSRIs are equally effective for typical cases, certain properties make them more or less appropriate for certain patients (see table). If one SSRI is ineffective, another SSRI can be substituted, or an antidepressant from a different class may be used instead.Tranylcypromineis often effective for depression refractory to sequential trials of other antidepressants; it should be given by a physician experienced in use of monoamine oxidase inhibitors (MAOIs). Psychologic support of patients and loved ones is particularly important in refractory cases. Insomnia, a common adverse effect of SSRIs, is managed by reducing the dose, giving the dose in the morning, or adding a low dose oftrazodoneor another sedating antidepressant at bedtime. Initial nausea and loose stools usually resolve, but throbbing headaches do not always remit, necessitating a change in medication class. An SSRI should be stopped if it causes agitation. When decreased libido, impotence, or anorgasmia occur during SSRI therapy, dose reduction or a change to aserotoninmodulator or anorepinephrine-dopaminereuptake inhibitor may help. SSRIs, which tend to stimulate many depressed patients, should be given in the morning. Giving the entire heterocyclic antidepressant dose at bedtime usually makes sedatives unnecessary, minimizes adverse effects during the day, and improves adherence. MAOIs are usually given in the morning and early afternoon to avoid excessive stimulation. Therapeutic response with most classes of antidepressants usually occurs in about 2 to 3 weeks (sometimes as early as 4 days or as late as 8 weeks). For a first episode of mild or moderate depression, the antidepressant should be given for 6 months, then tapered gradually over 2 months. If the episode is severe or is a recurrence or if there is suicidal risk, the dose that produces full remission should be continued as maintenance. For psychotic depression, the combination of an antidepressant and an Treatment is more effective than either used alone ( Continued therapy with an antidepressant for 6 to 12 months (up to 2 years in patients>50) is usually needed to prevent relapse. Most antidepressants, especially SSRIs, should be tapered off (by decreasing the dose by about 25%/week) rather than stopped abruptly; stopping SSRIs abruptly may result in discontinuation syndrome (nausea, chills, muscle aches, dizziness, anxiety, irritability, insomnia, fatigue). The likelihood and severity of withdrawal varies inversely with the half-life of the SSRI. 