Atypical Antidepressants - An Insight

Introduction

Atypical antidepressants do not fit into other classes of antidepressants. These antidepressants work uniquely. These antidepressants are usually prescribed if other types of antidepressants that have been tried do not work for the individual. However, based on the symptoms, atypical antidepressants can also be used as first-line drugs or if one experiences other mental health issues in addition to depression. Similar to other mental health medications, atypical antidepressants also work by restoring the balance of the neurotransmitters (chemical messengers). Each medication acts on different chemicals and influences them differently.

What Are the Different Types of Antidepressants?

Antidepressants are medications that are used to treat depression. They aid in uplifting one’s mood and ease the feeling of hopelessness and sadness. At times, they are also prescribed for insomnia and physical pain, to aid in quitting smoking, and so on. The following are the major types of antidepressants:

• SSRIs (Selective Serotonin Reuptake Inhibitors): SSRIs are the most commonly prescribed antidepressant. These drugs enhance how brain circuits utilize serotonin. Some of the common SSRIs include Escitalopram, Fluoxetine, Citalopram, Sertraline, and Fluvoxamine.

• SNRIs (Serotonin and Norepinephrine Reuptake Inhibitors): These drugs affect brain circuits that utilize both norepinephrine and serotonin. Some of the common SNRIs include Desvenlafaxine, Duloxetine, Venlafaxine, and Levomilnacipran.

• Tricyclic Antidepressants (TCAs): TCAs have been in use since the 1950s and are used to treat depression. The side effects associated with these drugs are more than the newer drugs used to treat depression. A few examples of TCAs include Doxepin, Amitriptyline, Imipramine, Amoxapine, Desipramine, Nortriptyline, Trimipramine, and Protriptyline.

• MAOIs (Monoamine Oxidase Inhibitors): MAOIs are early antidepressants and drugs like Phenelzine, Isocarboxazid, and Selegiline fall under this category.

• Atypical Antidepressants: Atypical antidepressants are prescribed if one’s depression is resistant to other types of antidepressants or if one experiences intolerable side effects from those drugs. Common examples of drugs in this category include Bupropion and Mirtazapine.

What Are the Common Types of Atypical Antidepressants That Are Approved by the FDA?

The following types of atypical antidepressants are approved by the Food and Drug Administration (FDA) to treat depression:

• Mirtazapine.

• Bupropion.

• Trazodone.

• Nefazodone.

• Vortioxetine.

• Vilazodone.

A new antidepressant named Esketamine is approved by the FDA for treating treatment-resistant depression. It comes in the form of a nasal spray and is used in combination with an oral antidepressant.

What Is the Mechanism of Action of Atypical Antidepressants?

Atypical antidepressants offer relief from symptoms of depression by acting on neurotransmitters (chemical messengers) that communicate between brain cells. Like the majority of antidepressants, atypical antidepressants act by making changes in the brain chemistry and communication in brain nerve cell circuitry that regulates mood, thereby offering relief from depression. Atypical antidepressants alter the levels of one or more neurotransmitters like serotonin, dopamine, or norepinephrine.

Are There Any Side Effects Associated With Atypical Antidepressants?

Side effects can occur with antidepressants, including atypical antidepressants. However, a few individuals may not experience any side effects. A few side effects may resolve with time, but a few others may require one to consult their physician and try a different medication. Since atypical antidepressants work in different ways, each has unique features and varying side effects. These side effects are as follows:

• Dry mouth, dizziness, or lightheadedness.

• A few antidepressants may aid in sleeping, while others might cause insomnia.

• A few antidepressants may cause constipation, while others may cause diarrhea.

• A few antidepressants may enhance one’s appetite, which can result in weight gain, while others may cause nausea.

• A few antidepressants are more susceptible than others to cause sexual side effects.

What Are the Safety Issues Associated With Atypical Antidepressants?

Atypical antidepressants are considered safe in most people. However, it might cause certain issues in certain circumstances, which are as follows:

• Bupropion is not advisable for use by those who have an eating disorder like anorexia, bulimia, or a seizure disorder.

• Mirtazapine has been linked with an increase in cholesterol levels. It is also associated with weight gain.

• Esketamine has the potential to cause serious side effects and, hence, must be administered by a psychiatrist or a primary care physician in close communication with a psychiatrist who is an expert in administering this drug.

• Nefazodone has been associated with liver failure in some individuals and should not be taken by those who have existing liver problems.

• Vilazodone and Vortioxetine may elevate the risk of bleeding, especially in those who take other medications that might exacerbate the risk of bleeding.

• Trazodone has been linked with rare cases of priapism (a persistent, usually painful erection that is not linked with sexual arousal). Rarely, Trazodone has been associated with heart rhythm issues like cardiac arrhythmias. Hence, if one has heart issues, it must be reported to the physician, and their opinion must be obtained before consuming the drug Trazodone.

Other points to be kept in mind while taking atypical antidepressants are:

• One must discuss with their physician about the benefits and risks of taking certain antidepressants during pregnancy and breastfeeding. If one is already on antidepressants and planning to become pregnant, then they must talk to their doctor regarding the possible risks. It must be remembered that one must never quit taking medications without consulting their physician as these might pose certain risks.

• When taking an antidepressant, one must inform their physician about any other over-the-counter or prescription medications, herbs, or supplements that one is taking. A few antidepressants can cause dangerous reactions if they are combined with herbal supplements or certain medications.

• In rare cases, an antidepressant can result in the accumulation of high levels of serotonin in the body. Serotonin syndrome usually occurs when two medications that elevate the level of serotonin are combined. These include a few herbal supplements like St. John’s wort, other antidepressants, certain headache or pain medications, and so on. Symptoms of serotonin syndrome include sweating, anxiety, agitation, confusion, high fever, tremors, lack of coordination, restlessness, rapid heart rate, and changes in blood pressure. One must consult their physician if they experience any of these symptoms.

Are Atypical Antidepressants Addictive?

Atypical antidepressants are not usually considered to be addictive. However, stopping an antidepressant all of a sudden or skipping several doses can result in withdrawal-like symptoms. Symptoms will differ based on how the drug works. This is also referred to as discontinuation syndrome. One must consult their physician to decrease the dosage gradually.

Conclusion

Depression is one of the most common mental health issues that can be treated in various ways. Certain antidepressants like SNRIs and SSRIs are usually prescribed as the first drugs of choice for treating depression. However, these antidepressants may not be effective for everyone, and in such cases, atypical antidepressants may be prescribed. Atypical antidepressants refer to a group of drugs that have various mechanisms of action and, hence, do not belong to other classes of antidepressants. Atypical antidepressants aid in treating depression by maintaining a balance amongst certain neurotransmitters in the brain, like dopamine, serotonin, and norepinephrine.