Which Antidepressant To Choose?

Antidepressants are medications that are primarily used to treat depressive disorders. They are also used to treat other mental health disorders such as anxiety, obsessive-compulsive disorder (OCD), and post-traumatic stress disorder (PTSD). Antidepressants work by altering chemical reactions in the brain that affect mood and emotions.

There are different types of antidepressants, and each has its mechanism of action. The choice of antidepressant to prescribe depends on the nature of the depressive disorder and the individual patient’s needs. The aim of this article is to provide information on the different types of antidepressants available and help you choose which antidepressant is right for you.

Types of Antidepressants

There are five main types of antidepressants:

  1. Selective serotonin reuptake inhibitors (SSRIs)
  2. Serotonin and norepinephrine reuptake inhibitors (SNRIs)
  3. Tricyclic antidepressants (TCAs)
  4. Monoamine oxidase inhibitors (MAOIs)
  5. Atypical antidepressants

Selective Serotonin Reuptake Inhibitors (SSRIs)

SSRIs are the most commonly prescribed antidepressants in Australia. They work by blocking the reabsorption of serotonin, a neurotransmitter that affects mood and emotions in the brain. This results in increased levels of serotonin in the brain, leading to an improvement in mood and a reduction in symptoms of depression.

Examples of SSRIs include:

  • Fluoxetine (Prozac)
  • Sertraline (Zoloft)
  • Paroxetine (Paxil)
  • Citalopram (Celexa)
  • Escitalopram (Lexapro)

SSRIs are generally well-tolerated and produce fewer side effects than other types of antidepressants. However, they may cause sexual dysfunction, weight gain, and gastrointestinal issues such as nausea, diarrhea, and constipation.

Serotonin and Norepinephrine Reuptake Inhibitors (SNRIs)

SNRIs are another type of antidepressant that works by increasing the levels of both serotonin and norepinephrine in the brain. Norepinephrine is a neurotransmitter that is involved in regulating the body’s response to stress.

Examples of SNRIs include:

  • Venlafaxine (Effexor)
  • Duloxetine (Cymbalta)
  • Desvenlafaxine (Pristiq)

SNRIs may cause similar side effects to SSRIs, such as nausea, weight gain, and sexual dysfunction. They may also cause agitation, anxiety, and gastrointestinal issues.

Tricyclic Antidepressants (TCAs)

TCAs are one of the oldest classes of antidepressants. They work by blocking the reuptake of neurotransmitters such as serotonin and norepinephrine, leading to an increase in the levels of these chemicals in the brain.

Examples of TCAs include:

  • Amitriptyline (Elavil)
  • Imipramine (Tofranil)
  • Nortriptyline (Pamelor)
  • Doxepin (Sinequan)
  • Clomipramine (Anafranil)

TCAs are effective in treating depression, but they also have a higher risk of side effects than newer antidepressants. The side effects of TCAs may include dry mouth, blurred vision, constipation, urinary retention, and dizziness.

Monoamine Oxidase Inhibitors (MAOIs)

MAOIs are a rare type of antidepressant that works by blocking the action of monoamine oxidase, an enzyme that breaks down neurotransmitters such as serotonin and norepinephrine in the brain. MAOIs are only used when other antidepressants have failed to produce a response.

Examples of MAOIs include:

  • Phenelzine (Nardil)
  • Tranylcypromine (Parnate)
  • Isocarboxazid (Marplan)

MAOIs have potentially life-threatening side effects, including high blood pressure, rapid heartbeat, and seizures. Patients taking MAOIs must also adhere to a strict diet to avoid interacting with certain foods and medications.

Atypical Antidepressants

Atypical antidepressants are a category of antidepressants that do not fit into the other categories. They work by altering the levels of neurotransmitters such as norepinephrine, dopamine, and serotonin in the brain.

Examples of atypical antidepressants include:

  • Bupropion (Wellbutrin)
  • Trazodone (Desyrel)
  • Mirtazapine (Remeron)
  • Nefazodone (Serzone)

Atypical antidepressants have fewer side effects than TCAs and MAOIs but may still cause drowsiness, dry mouth, dizziness, and constipation. Bupropion, in particular, may increase the risk of seizures in some patients.

Choosing the Right Antidepressant

Choosing the right antidepressant to treat depression depends on several factors, including the nature of the depressive disorder, the patient’s medical history and current health status, and the potential side effects of the medication.

SSRIs are often the first-choice antidepressants due to their effectiveness, low risk of side effects, and tolerability. They are especially useful for treating depression associated with anxiety disorders, as they have anti-anxiety properties. SNRIs are another option for patients who do not respond to SSRIs or who have both depression and pain conditions.

TCA antidepressants may be effective for patients with treatment-resistant depression or severe depression. However, they have a higher risk of side effects, so they are not typically used as a first-line treatment.

MAOIs are rarely used today, as they have a high risk of side effects and interactions with certain medications and foods. However, they may be effective for patients with treatment-resistant depression who do not respond to other antidepressants.

Atypical antidepressants are a broad category that includes several different medications that work differently. They may be useful for patients with specific symptoms, such as insomnia or weight gain, that other antidepressants may exacerbate.

The Bottom Line

The choice of antidepressant depends on several factors, including the nature of the depressive disorder, the patient’s medical history and current health status, and the potential side effects of the medication. While some antidepressants are better suited for specific symptoms than others, the most effective antidepressant varies from person to person. Therefore, it is important to work with your healthcare provider to find the medication that is right for you.

If you are struggling with depression or other mental health conditions, please seek the help of a medical professional. Remember, you are not alone, and there is help available.



1. How do I know which antidepressant to choose?

Choosing an antidepressant can be challenging, and it largely depends on various factors such as your symptoms, medical history, age, and lifestyle. Your doctor or healthcare provider can help you choose the most suitable antidepressant for your condition based on your symptoms and personal preferences.

2. What are the different types of antidepressants available?

There are various types of antidepressants available, including selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs), monoamine oxidase inhibitors (MAOIs), and atypical antidepressants. Each type works differently and may have different side effects, so it’s essential to work with your doctor to choose the right one for you.

3. Can I switch between different antidepressants?

Yes, it’s possible to switch between different antidepressants, but it’s crucial to do it under your doctor’s supervision. Abruptly stopping your medication or changing it without consulting your healthcare provider can cause withdrawal symptoms or exacerbate your symptoms. Your doctor may gradually taper off your medication while starting a new one to ensure a seamless transition.


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2. Malhi, G. S., Bassett, D., Boyce, P., Bryant, R., Fitzgerald, P. B., Fritz, K., & Hopwood, M. J. (2016). Australian and New Zealand clinical practice guidelines for the treatment of depression. Australian & New Zealand Journal of Psychiatry, 50(9), 1-117. doi:10.1177/0004867416660253

3. Montgomery, S. A. (2016). Selecting the most appropriate antidepressant: A review of key guidelines and recommendations. Prim Care Companion CNS Disord, 18(3). doi:10.4088/PCC.16f02014