Several types of medications can be used to treat depression. Most of these are called antidepressants. They work by restoring the balance of the chemicals in your brain.

How do antidepressants work?

There are a few different types (or “classes”) of antidepressants. They each work by restoring the balance of the chemicals in your brain, but each medication works on different chemicals and affects them differently.

The brain chemicals we’re talking about are called neurotransmitters. They send messages from one brain cell to the next. Different neurotransmitters send different types of messages. The most important ones for understanding antidepressants are:

• Serotonin, which affects your mood, energy level, appetite, and sleep
• Dopamine, which affects motivation and pleasure—sometimes called the “feel-good chemical”
• Norepinephrine, which affects your energy level, focus and attention. Related to adrenaline and has similar effects.

Each antidepressant has slightly different effects on each of these neurotransmitters. This is why the same medication that works for you might not work the same for someone else.

How do I take an antidepressant?

Antidepressants are taken daily. They often take several weeks before they have a noticeable effect. You can’t just take an antidepressant every once in a while, on days where you feel especially depressed.

You might be tempted to stop taking them as soon as you feel better, thinking that you’ve been cured. Unfortunately, antidepressants are not a cure for depression—they are a way of managing it, not a way of making it go away permanently. Some people are able to eventually stop taking antidepressants, but there’s no shame in taking them for long periods of time or even for your whole life!

If you do decide to stop taking an antidepressant, it’s best to talk to your doctor first. Your doctor can help you reduce the dosage gradually, which will reduce withdrawal symptoms. (You can often do this by cutting your tablets in half for a few weeks, then into fourths for a few more weeks.) They may also help you find an alternative that has fewer side effects or is more effective.

Side effects

All mental health medications have the potential for side effects [4]. Each medication is different—for information about the side effects of a specific type of antidepressant, read the articles on SSRIs, SNRIs, TCAs, MAOIs, and/or atypical antidepressants.

Common side effects of antidepressants include:

• Changes in your sleep, appetite, weight, or sex drive
• Feeling nauseous or dizzy
• Headaches

In rare cases, antidepressants can actually make you feel more depressed, or have suicidal thoughts. If this happens, talk to your psychiatrist right away.

Most antidepressants have the potential to cause serotonin syndrome, which is rare but serious. Serotonin syndrome happens when the serotonin levels in your brain get too high. It usually happens when you are taking more than one medication or supplement that boosts serotonin. Symptoms include:

• Feeling confused and agitated
• Twitching muscles
• Sweating or shivering
• Diarrhea

In the most severe but very rare cases, it can include:

• Seizures
• Irregular heartbeat
• Loss of consciousness

Types of antidepressants

There are many different types of antidepressants. Some of them are very similar to each other. Medications that work in similar ways are grouped together into classes. Let’s look at some of the most common classes of antidepressants and how they work.

(Remember: antidepressants work by balancing the neurotransmitters in your brain, mainly serotonin, dopamine, and norepinephrine.)

Selective Serotonin Reuptake Inhibitors (SSRIs)

This is the most commonly prescribed type of antidepressant. Chances are, if you go to your family doctor and say you are depressed, they will prescribe you an SSRI. Other types of antidepressants are usually given if SSRIs don’t seem to help.

SSRIs lift your mood by boosting the serotonin levels in your brain. They can be used to treat many mental health conditions, including depression, anxiety, obsessive-compulsive disorder (OCD), and post-traumatic stress disorder (PTSD).

For more information, check out our full article on SSRIs.

Serotonin and Norepinephrine Reuptake Inhibitors (SNRIs)

SNRIs are similar to SSRIs, except that in addition to serotonin, they also boost norepinephrine. In addition to depression and anxiety, SNRIs can also treat chronic pain and ADHD .

For more information, check out our full article on SNRIs.

Tricyclic Antidepressants (TCAs)

TCAs are an older class of antidepressants. They are now less common than SSRIs and SNRIs, but they are still used if other types of antidepressants don’t seem to be working. They can also be an option for ADHD .

For more information, check out our full article on TCAs.

Monoamine Oxidase Inhibitors (MAOIs)

MAOIs are the oldest type of antidepressants on this list. MAOIs can interact with food, so being on them often involves dietary restrictions. They also interact with a lot of other medications. For these reasons, they’re no longer used very commonly .

Still, MAOIs can be helpful if other types of antidepressants haven’t worked. They are sometimes used to treat bipolar disorder, or to treat neurological conditions such as Parkinson’s disease.

They can also be helpful with atypical depression, or “depression with atypical features.”

For more information, check out our full article on MAOIs.

Atypical antidepressants

Some antidepressants don’t fit into any of the above categories. These are commonly used to target specific symptoms, to avoid side effects, or when other antidepressants don’t seem to be working. Most of them are less likely to cause sexual side effects than other types of antidepressants.

• Bupropion  boosts dopamine and norepinephrine. Unlike most antidepressants, it has no effect on serotonin. It is often prescribed to target specific symptoms, like oversleeping, weight gain, fatigue, and trouble concentrating, or to counteract the side effects of other antidepressants.
• Trazodone is an antidepressant, but it’s also commonly prescribed for people who have trouble sleeping or who experience nightmares due to PTSD .
• Mirtazapine is also prescribed as a sleep aid. It can cause an increase in appetite and weight gain, which can be a negative side effect—or a plus, for people who are underweight or have an eating disorder.
• Vortioxetine is similar to other antidepressants that work by boosting serotonin levels in the brain.
• Ketamine and esketamine are medications that have mainly been used for anesthesia and pain management. In recent years, these have begun to be used to treat severe or treatment-resistant depression (TRD).

For more information, check out our full article on atypical antidepressants.

Other treatments for depression

In addition to antidepressants, there are other types of medications that can sometimes help with depression. Many of these are designed to treat other conditions, such as anxiety or bipolar disorder. Atypical antipsychotics are a common example. Many people who have been diagnosed with depression also have symptoms of other mental and physical health conditions. Treating these other conditions can help with depression as well.

Medication is also not the only treatment for depression. Therapy is helpful for many people. Lifestyle changes can also help: getting more sleep, eating foods that help you feel energized and healthy, doing enjoyable activities, and getting more exercise are good places to start.