“Mood stabilizer” has a variety of meanings attached to it. For the lay public, any medication that helps even one’s moods, including the antidepressant medications, is a mood stabilizer. For most psychiatrists, mood stabilizer includes a class of medications that treat and prevent mania.
These medications typically include anticonvulsant medications such as valproic acid and carbamazepine; atypical antipsychotic medications such as olanzapine, quetiapine, risperidone, and aripip-razole; and lithium. However, the definition of a true mood stabilizer is a medication that treats and prevents both depression and mania. No true mood stabilizer by that definition exists.
Perhaps lithium is the closest to meeting that definition, although it does not truly compare with antidepressants in effectively treating depression. Other antimanic medications that are never thought of as mood stabilizers include the anti-anxiety medications. At one time, alprazolam was used to treat certain forms of depression as well as anxiety and mania.
Thus it is important to understand that when a psychiatrist adds a mood stabilizer to an antidepressant, one needs to know exactly what class of agent is being prescribed and for what purpose. Many times patients may have associated symptoms with their depression (such as psychosis) and therefore an atypical antipsychotic medication is an appropriate addition to the antidepressant.
Still other patients may experience a great deal of anxiety and panic, in which case the addition of an antianxiety agent may be appropriate. Some patients may never have had a manic episode, but some of their symptoms and family history are strongly suggestive of an underlying bipolar disorder.
Under these circumstances the safest medication to prescribe may be a mood stabilizer alone, unless the depression is severe enough to warrant aggressive care, in which case the psychiatrist may prescribe an antidepressant with an anticonvulsant, lithium, or atypical antipsychotic as a preventative measure. Finally, some patients may achieve only a partial response to the antidepressant.
When a partial response is achieved, the psychiatrist will typically add another medication to augment the primary medication’s response rather than switch the medication altogether. Aripiprazole has an FDA indication for use as an augmenting agent to antidepressant medication for the treatment of major depression.