All about antidepressants

Antidepressants can help relieve the symptoms of depression and anxiety. Common examples include selective serotonin reuptake inhibitors (SSRIs), such as fluoxetine (Prozac), and serotonin-norepinephrine reuptake inhibitors (SNRIs), such as duloxetine (Cymbalta).

Antidepressants work by increasing neurotransmitters in the brain. Experts believe these brain chemicals are responsible for changes in mood and behavior.

This article covers the types of antidepressants, how they work, their side effects, other uses, and alternative options.


Doctors tend to divide antidepressants into different types. These include:

Selective serotonin reuptake inhibitors (SSRIs)

SSRIs are a first-line

 treatment option for depression.

Examples of SSRIs include:

  • citalopram 
  • escitalopram 
  • fluoxetine 
  • fluvoxamine (Luvox)
  • paroxetine 
  • sertraline

Serotonin-norepinephrine reuptake inhibitors (SNRIs)

SNRIs are a newer class of antidepressants compared with SSRIs. However, they work similarly.

Doctors may prescribe SNRIs for:

  • attention deficit hyperactivity disorder (ADHD)
  • obsessive-compulsive disorder (OCD)
  • anxiety disorders
  • menopausal symptoms
  • fibromyalgia
  • chronic neuropathic pain

Examples of SNRIs include:

  • duloxetine 
  • venlafaxine 
  • desvenlafaxine (Pristiq)

Side effects

All drugs have side effects, not just antidepressants.

Different antidepressants have different side effects. However, not everyone experiences them.

SSRI and SNRI side effects

SSRIs and SNRIs can lead to:

  • nausea
  • indigestion
  • headache
  • sexual dysfunction

SNRIs can also increase blood pressure. A person with a serious heart condition should not take the SNRI venlafaxine.

TCA side effects

TCAs may have the following side effects:

  • dry mouth
  • tremor
  • fast heart rate
  • constipation
  • insomnia
  • weight gain

MAOI side effects

MAOIs can interact with other drugs. For example, if a person combines an MAOI with an SSRI, it could lead to serotonin syndrome. Serotonin syndrome is a serious condition in which a person has too much serotonin in their body.

MAOIs can also lead to:

  • dry mouth
  • diarrhea
  • nausea
  • drowsiness
  • constipation
  • dizziness
  • insomnia
  • lightheadedness
  • sexual dysfunction

MAOIs prevent the breakdown of tyramine. If a person consumes foods that contain tyramine, such as sausages, dried fish, and overripe fruit, it can lead to a hypertensive crisis. This is a severe increase in blood pressure that can lead to a stroke.

NaSSA side effects

These antidepressants can lead to side effects similar to SSRIs and SNRIs. NaSSAs can also cause drowsiness and weight gain. They are less likely to cause sexual dysfunction.


Antidepressants tend to be effective. However, everyone responds to medication differently.

According to the Institute for Quality and Efficiency in Health Care, 40–60% of people who took an SSRI or SNRI for depression noticed some symptom relief within 6–8 weeks.

The research notes that the more severe the depression, the greater the benefits of antidepressants may be.

Alternative options

People may wish to try the following:


People with depression may wish to undergo therapy. Types of therapy that can help treat depression include:

  • cognitive behavioral therapy (CBT)
  • interpersonal therapy
  • problem-solving therapy

Diet and exercise

The Centers for Disease Control and Prevention (CDC) notes that regular physical activity can reduce a person’s risk of depression. People may wish to try three exercise sessions per week for 12–24 weeks.

People may also benefit from eating a balanced, nutritious diet full of fresh and whole foods. They may wish to avoid or limit refined and processed foods.

Frequently asked questions

Below are some commonly asked questions about antidepressants.

Which antidepressant is right for me?

There are many types of antidepressants. They all work differently and have different benefits, risks, and side effects.

A person can speak with a doctor about their individual circumstances. The doctor can help them find the best treatment option for them.

Are antidepressants safe during pregnancy?

The CDC notes there is a link between taking SSRIs during pregnancy and congenital abnormalities. However, this risk is very low.

For some people, the risks associated with stopping the medication are higher than those associated with continuing to take it.

If a person is pregnant and wishes to continue or begin taking antidepressants, they should speak with a doctor.

Tiny amounts of some antidepressants can enter breast milk. However, the CDC states most antidepressants will have no effect on milk supply or the child’s well-being.

How long should I stay on antidepressants?

According to the NHS, doctors typically suggest a person takes antidepressants for at least 6 months.

People should take their antidepressants exactly as their doctor has prescribed.


Antidepressants can help relieve symptoms of conditions such as depression and anxiety disorders. They work by increasing neurotransmitters in the brain.

Examples of antidepressants include SSRIs, SNRIs, TCAs, and NaSSAs. MAOIs may also be an option, though doctors prescribe these less often due to the risk of adverse side effects.

It can take several weeks for antidepressants to start working. People may experience side effects.

Alternatives to antidepressants include therapy, diet and exercise, and St. John’s wort. However, depression is a serious condition that may need professional treatment. Anyone who experiences the symptoms of depression should speak with a doctor.