Antidepressant and Mood Stabilizer Drug Therapy

Antidepressants are medications primarily used to treat major depressive disorder, which is a condition associated with a persistent feeling of sadness and loss of interest in everyday activities. There are five classes of antidepressant medications, including tricyclic antidepressants, or TCAs, selective serotonin reuptake inhibitors, or SSRIs, serotonin and norepinephrine reuptake inhibitors, or SNRIs, monoamine oxidase inhibitors, or MAOIs, and atypical antidepressants.

Mood stabilizers are used to treat bipolar disorder, which is manifested by alterations in mood and behavior, vacillating between mania and depression. Examples of mood stabilizers include lithium, carbamazepine, valproic acid, divalproex, and lamotrigine.

First, let’s focus on the SSRI sertraline. Sertraline is taken orally, and is rapidly absorbed into the bloodstream. Once it travels to the brain it inhibits the reuptake of serotonin, increasing the level of serotonin within the synaptic cleft.

Now, sertraline affects different types of receptors in the brain, such as those that regulate sleep, appetite, or sexual function, so sertraline can cause insomnia, loss of appetite or weight gain, and sexual dysfunction. Sertraline can also cause hyponatremia, possibly by increasing the secretion of antidiuretic hormone. Some other side effects are anxiety, nausea, diarrhea, constipation, and bruxism, or teeth clenching and grinding.

Now, as far as contraindications and cautions go, SSRIs like sertraline can increase the risk of bleeding, especially if given along with antiplatelet or anticoagulant medications.

Additionally, sertraline can cause serotonin syndrome, which usually occurs when combined with other antidepressants that increase the level of serotonin in the brain, especially MAOIs. Patients that develop serotonin syndrome typically present with skin flushing, hyperthermia, agitation, muscle rigidity, seizures, altered mental status, or even coma.

Sertraline should be used with caution during pregnancy, as well as in patients with hepatic impairment, acute angle-closure glaucoma, and risk factors for QT prolongation. An important Black Box warning for all antidepressants is that they can increase the risk of suicidal thinking in children, adolescents, and young adults. So patients will need to be monitored closely, especially when starting treatment or changing dosage.

Okay, let’s switch gears and talk about lithium. Lithium is taken orally and is rapidly absorbed and widely distributed throughout the body. It’s thought to work by altering ion transport across cell membranes, allowing sodium ion transport into nerve cells, and resulting in a change in catecholamine metabolism.