Choosing the optimal mood stabilizer is crucial for treating bipolar disorder effectively. It’s important to consider the specific symptoms and needs of the individual patient, as well as the potential side effects and interactions with other medications. The goal is to find a medication that provides effective symptom control without causing additional problems or complications.
At our CHMC Clinic in Dubai, our expert psychiatrist, Dr. Kowal, provides personalized therapy for Bipolar Disorder
Read more about Bipolar Disorder
- Bipolar Disorder, Diagnostic & Treatment
- What is Mania and Hypomania?
- Cyclothymic Disorder
- History of Treatment of Bipolar Disorder
- CANMAT Guidelines of Bipolar Disorder Treatment with Medication
- Treatment with Lithium of Bipolar Disorder
Classification of Mood Stabilizers for Treatment of Bipolar Disorder
The following classification of mood-stabilizing medication was proposed by the researchers Ketter & Calabrese:
• Type A: lithium, valproic acid, carbamazepine, olanzapine, risperidone, quetiapine, ziprasidone, aripiprazole
• Type B: lithium, lamotrigine, quetiapine
The above classification is helpful to select the proper medication. The key roles for choosing a mood stabilizer are:
Type A mood stabilizers work against manic, hypomanic, and mixed episodes, while Type B stabilizers work against depressive and sub-depressive episodes. Apart from that, they don’t cause a shift to another phase or to rapid cycling.
Anticonvulsants with Mood Stabilizing Effect in Bipolar Disorder
For decades, lithium salts were the sole option for relapse prevention in bipolar disorder. However, since the early 1990s, additional pharmacological therapies, particularly anticonvulsants, have been developed, expanding treatment options.
Valproic Acid
It is a mood stabilizer that helps control symptoms during the manic or mixed phases of bipolar disorder. The positive effect of valproic acid on mood swings was already known in the 1960s but then fell into oblivion. Only in the early 1990s were studies conducted in the United States, and valproic acid has since been used in the treatment of bipolar disorder.
Valproate works by increasing the level of a neurotransmitter called GABA in the brain, which helps to calm the overactive circuits that contribute to bipolar symptoms.
Valproate is mostly used in the treatment of acute manic episodes. Some studies also demonstrate its relapse-preventing effect for both manic and depressive episodes. Valproic acid is only approved for the treatment of manic episodes but can be used off-label for the treatment of bipolar depression. Recently published research data suggested that valproate might be more effective than lithium for treatment of mixed states and rapid cycling in bipolar disorder.
Valproic acid is often used in combination with other mood stabilizers or antipsychotics to reduce the risk of relapse. Valproic acid is generally safe and effective. However, regular monitoring with blood tests and clinical assessments excludes potential side effects.
The most common side effect of valproic acid might be weight gain.
Lamotrigine
Similar to other mood stabilizers, except lithium, lamotrigine is a newer generation antiepileptic drug. It has been used for years as a mood stabilizer in bipolar I and II, especially in prophylaxis. It received regulatory approval for the treatment and prevention of bipolar depression in over 30 countries. Recent studies have shown that lamotrigine is exceptionally effective in the treatment of bipolar I depression.
Lamotrigine inhibits sodium channels in the central nervous system, leading to the release of glutamate. It exerts a positive effect on the corticolimbic network function, which is a result of abnormal activities of the circuits in bipolar depression. Further research is needed to confirm its efficacy in treating bipolar II disorder and rapid cycling.
Experience suggests that only a higher dose of 200-400 mg/day effectively prevents relapse. It is necessary to start with a low dose of 25 mg and gradually increase it in weekly intervals. Lamotrigine is usually well tolerated by the patient without major side effects. It can also be used during pregnancy in women with bipolar disorder. In rare cases, lamotrigine can cause an allergic reaction to the skin. Therefore, the dosage of lamotrigine should be slowly increased over a few weeks. Because of this limitation, Lamotrigine can’t be used immediately in sufficient dosage in the treatment of acute mania.
Carbamazepine
The anticonvulsant effect of carbamazepine has been known for 30 years, but its use as a mood stabilizer in bipolar disorder began in the mid-nineties. Carbamazepine works by blocking sodium channels in nerve cells. In 1980, it was discovered in Japan that Carbamazepine also has an anti-manic and relapse-preventing effect in bipolar disorder. Carbamazepine is generally well tolerated, creating occasional side effects such as allergic skin reactions. Its main problem is the negative pharmacokinetic interactions with other medications, which can lead to a sudden drop in their efficacy. The results of double-blind studies comparing the efficacy of carbamazepine with lithium demonstrated a clear superiority of the latter. For these reasons, carbamazepine is being used less frequently and only as a second-line option for relapse prevention in bipolar disorder.
Lithium
Lithium has the broadest spectrum of effectiveness in the long-term pharmacological treatment of bipolar disorder. However, its main drawbacks are its lack of efficacy in acute depressive episodes and its narrow therapeutic range, which necessitates regular lithium blood level monitoring.
Lithium remains the gold standard for preventing relapse in bipolar disorders. Its prophylactic and anti-manic properties are well established. Based on current knowledge, its strength lies more in preventing manic episodes than depressive ones.
When it comes to acute bipolar depression, lithium has been proven effective only in combination with other medications.