Mood stabilizers are a class of drugs that do exactly what their name says – they stabilize our mood. They’re named after the effect they bring about, rather than their mechanism. They are prescribed during diseases that cause mood swings in a person, and therefore require an external drug to stabilize the mood. These drugs are most commonly used for Bipolar Disorder.
This is a mental disorder that is characterized by alternating periods of mania or hypomania and depression. Mania refers to periods of heightened excitement, aggression and arousal. This high can be euphoric or irritated in nature, but with increasing intensity of the mania, the irritation is more pronounced, thus leading to increased aggression. Depression, as expected, manifests in periods of low energy and excitement. Depression and mania are often considered mirror images of each other.
People suffering from Bipolar Disorder often have trouble keeping up with a normal social and professional life due to their exaggerated mood swings.
These are drugs that help control the mood swings of a person suffering from Bipolar Disorder I and II. They are also used in patients with borderline personality disorder and schizophrenia. Rather than single drugs, they are used in combination to give better results. Most drugs treat a particular aspect of the disorder. Lithium, the first FDA approved drug for Bipolar Disorder, is better at treating the symptoms of mania, while lamotrigine is more effective in treating depression. Therefore, the drugs are used in combination. Their doses are also altered based on the intensity of the mood swings and whether they are being used as maintenance drugs.
Some anticonvulsants and antipsychotics also help in controlling these mood swings. These are also prescribed along with other drugs, even though the patient may not exhibit any specific psychotic symptoms or seizures.
It is essential to continue using these medicines, even if a patient feels completely fine. This prevents any relapses, and usually the patient feels fine as a result of the drugs.
Mechanism of Mood Stabilizers
Various drugs work by affecting various aspects of the body’s metabolism. Therefore, there is no standard mechanism. It is also important to realize that the exact mechanism of these drugs is not understood completely, and all we have right now are potential hypotheses.
Lithium, the most commonly used drug for Bipolar Disorder, is supposed to inhibit the enzyme GSK3B. This enzyme, among other functions, is involved in neuronal cell development. It is a known fact that abnormalities in its expression and regulation make a person susceptible to Bipolar Disorder. Therefore, this is one possible way that lithium works. It is also suspected to increase serotonin secretion.
Certain drugs also affect the secretion of other neurotransmitters, like glutamate.
Another popular theory is the effect of these drugs on the arachidonic acid cascade. Arachidonic acid is a polyunsaturated fatty acid that is found in the phospholipid membranes of cells, especially in the brain, muscles and liver. This acid is metabolized by various enzymes to form various products, all of which have different functions. This process of the formation of the various products is known as the Arachidonic acid cascade.
Arachidonic acid is essential for neurological development in infants. It also performs a number of key functions in the brain, such as protecting the brain from oxidative stress, and the activation of a protein involved in the repair of neurons. Abnormality in the metabolism of Arachidonic acid, or the Arachidonic cascade, can lead to brain disorders like Bipolar Disorder or Alzheimer’s disease. Therefore, certain drugs supposedly target this cascade, thus bringing about the effect of mood stabilization.
Proper understanding of the exact mechanism of the disorder and the drugs that serve as mood stabilizers will enable us to develop better drugs. Currently, there is no single drug that is used. The choice of drug varies from person to person. However, until we develop better drugs, these mood stabilizers are our best option, and they have certainly been working so far!
- National Center for Biotechnology Information (NCBI) (Link 1)
- National Center for Biotechnology Information (NCBI) (Link 2)