The term "mood stabilizer" does not describe a mechanism but an effect. More precise terminology based on
pharmacology is used to further classify these agents. Drugs commonly classed as mood stabilizers include the drugs listed below.
Mineral Lithium Lithium is the "classic" mood stabilizer, the first to be approved by the
United States Food and Drug Administration (FDA), and still popular in treatment.
Therapeutic drug monitoring is required to ensure lithium levels remain in the therapeutic range: 0.6 to 0.8 mmol/L for maintenance treatment or 0.8–1.0 mmol/L for acute mania. Signs and symptoms of toxicity include nausea, vomiting, diarrhea, and
ataxia. The most common side effects are lethargy and weight gain (up to ). The less common side effects of using lithium are blurred vision, a slight tremble in the hands, and a feeling of being mildly ill (
malaise). In general, these side effects occur in the first few weeks after commencing lithium treatment. These symptoms can often be improved by lowering the dose. Long-term lithium therapy also carries risks such as hypothyroidism and chronic kidney disease, requiring periodic monitoring of thyroid and renal function. It is also one of the few drugs with proven anti-suicidal properties, making it unique among psychiatric medications.
Anticonvulsants Anticonvulsants, also known as antiseizure medications, are agents originally developed for treating
epilepsy and
seizure disorders. In the 1970s, clinical trials demonstrated that certain anticonvulsants were effective in mood stabilization, subsequently, these medications were adopted in psychiatry for treating
mood disorders. This class of medication is divided into first generation and second generation agents based on the time of their development, with the second generation agents having lesser adverse effects and better tolerability compared to the first generation.
Valproate Valproate is a first generation anticonvulsant agent. This drug is considered as the first line treatment for both
acute mania and maintenance of
bipolar disorder. It primarily acts by inhibiting
GABA transaminase and increasing GABAergic activity, thereby decreasing neuronal excitability. It can also inactivate sodium and calcium channels. Weight gain is possible. It is recommended that women of childbearing age should avoid using valproate due its
teratogenic potential, including the increased risk of
neural tube defects, even with
folic acid supplementation. In the
United Kingdom and
European Union, valproate has been restricted for women and men under age 55 due to pregnancy and fertility concerns.
Carbamazepine Carbamazepine is also a first generation anticonvulsant. It is considered second-line for bipolar disorder due to its side effects, including gastrointestinal symptoms,
Stevens‐Johnson syndrome,
toxic epidermal necrolysis, and weight gain. It
interacts with many medications, including other mood stabilizers (e.g., lamotrigine) and
antipsychotics (e.g.,
quetiapine). Lamotrigine can cause
Stevens–Johnson syndrome, a very rare but potentially fatal skin condition. There is insufficient evidence to support the use of various other anticonvulsants, such as
gabapentin and
topiramate, as mood stabilizers.
Antipsychotics Some
atypical antipsychotics (
aripiprazole,
asenapine,
cariprazine,
lurasidone,
olanzapine,
paliperidone,
quetiapine,
risperidone, and
ziprasidone) also have mood-stabilizing effects and are thus commonly prescribed even when
psychotic symptoms are absent.
Other Omega-3 fatty acids It is also conjectured that
omega-3 fatty acids may have mood-stabilizing effects. Compared with placebo, omega-3 fatty acids appear better able to augment known mood stabilizers in reducing depressive—but perhaps not manic—symptoms of bipolar disorder; additional trials would be needed to establish the effects of omega-3 fatty acids alone.'''' Recent studies suggest that preparations with a higher ratio of
eicosapentaenoic acid (EPA) to
docosahexaenoic acid (DHA) -types of omega-3 fatty acids- are more effective in improving depressive symptoms, while effects on mania remain inconsistent.
Levothyroxine It is known that even subclinical
hypothyroidism can blunt a patient's response to both mood stabilizers and antidepressants. Furthermore, preliminary research into the use of thyroid augmentation in patients with refractory and rapid-cycling bipolar disorder has been positive, showing a slowing in cycle frequency and reduction in symptoms. Most studies have been conducted on an open-label basis. One large, controlled study of a 300 mcg daily dose of
levothyroxine (T4) found it superior to placebo in the setting of bipolar disorder. In general, studies have shown T4 to be well tolerated and to show effectiveness even in patients without overt hypothyroidism. It is reported that supraphysiological doses of levothyroxine may be particularly beneficial in women with treatment-resistant bipolar depression, although long-term safety still needs further evaluation. Hypothyroidism is common among patients with bipolar disorder regardless of the mood stabilizer used.
Combination therapy In routine practice, monotherapy is often insufficiently effective for acute and/or maintenance therapy. Thus, most patients are placed on
combination therapy. ==Relationship to Antidepressants==