Antidepressants

Also called: SSRIs · Selective serotonin reuptake inhibitors · Tricyclic antidepressants

About Antidepressants

Antidepressants are prescription medicines to treat depression. Depression is more than feeling a little sad or "blue" for a few days. It's a very common, serious medical illness that affects your mood and general mental health It can make you feel tired, hopeless, worried, or fearful. It can change your thinking, sleeping, and eating. Depression may make some people think about ending their lives.

But antidepressants can help many people who have depression. Researchers think antidepressants may help improve the way your brain uses certain chemicals that control mood or stress.

A health care provider may prescribe antidepressants for anxiety, chronic pain, or insomnia. Sometimes providers also prescribe antidepressants for other conditions.

There are many types of antidepressants. Each one works differently. Providers usually prescribe newer antidepressants first because they don't cause as many side effects as older types. They also seem to help more kinds of depression and anxiety problems.

Most of the newer antidepressants belong to one of these three groups:

• Selective serotonin reuptake inhibitors (SSRIs)
• Serotonin and norepinephrine reuptake inhibitors (SNRIs)
• Atypical antidepressants, which are newer antidepressants that don't fit into the other groups

If these antidepressants don't help, your provider might suggest one of the older antidepressants. The older types include tricyclic antidepressants (TCAs), tetracyclics, and monoamine oxidase inhibitors (MAOIs). Even though these antidepressants may cause more serious side effects, the benefits may outweigh the risks for some people.

Our bodies and brains all work differently. That means one antidepressant won't work for everyone. You may need to try two or more medicines before you find one that works for you.

Your provider will work with you to choose the best option to try first. You'll consider questions such as:

• Which symptoms bother you most? Some antidepressants may do a better job helping specific symptoms, such as trouble sleeping.
• What other medicines and supplements do you take? Some antidepressants can cause problems if you take them with certain medicines and herbs.
• Did a certain antidepressant work well for a close relative? An antidepressant that helped a parent, brother, or sister could be a good choice for you, too.
• Do you have other health conditions? Certain antidepressants can make some other conditions better or worse. Any other conditions that you have will be part of choosing your depression treatment.
• Are you pregnant, planning for pregnancy, or breastfeeding? If so, your provider will help you find a way to treat your depression that's safe for you and your baby.

Antidepressants usually take 4 to 8 weeks to work, so you'll need to be patient. You may notice that some problems, such as sleeping and eating, get better before your mood improves. That's a good sign. You may just need to give the medicine a little more time to do its job.

Sometimes an antidepressant helps at first, but symptoms return while you're still taking it. But there's usually another one you can try. To get more relief from depression, your provider may suggest combining two antidepressants, using another kind of medicine with an antidepressant, or adding talk therapy or other approaches to improve your mental health.

When an antidepressant starts to work, you and your provider can decide how long you need to stay on it. The typical length of treatment is 6 to 12 months, but some people may stay on antidepressants for much longer.

Not everyone has side effects from antidepressants. But if you do have them, they're usually mild and may get better over time as your body gets used to the new medicine.

The most common side effects from antidepressants include:

• Nausea and vomiting
• Weight gain
• Diarrhea
• Sleepiness
• Sexual problems, such as a lack of desire or ability to have sex

When thinking about side effects, it's important to remember that there are also risks from not treating depression. Your provider can help you think through the pros and cons of all your options.

If you have any side effects from antidepressants, your provider may suggest ways to manage them while you wait to see if the antidepressant will work. If the side effects bother you too much, you may need to change antidepressants. But you should never change your dose or stop taking an antidepressant on your own.

If you have serious problems or notice any changes that worry you, such as new or worsening symptoms, unusual changes in your mood, or you start acting differently, call your provider right away.

In some cases, children, teenagers, and young adults under 25 may be more likely to think about hurting or killing themselves when starting antidepressants or when the dose is changed. Get medical help right away if this happens.

Antidepressants are generally safe when you use them correctly:

• Tell your provider about everything you take. That includes medicines, herbs, supplements, and over-the-counter medicines you take, such as pain relievers and decongestants. Be honest about recreational drugs and alcohol, too.
• Try to get all your medicines from the same pharmacy. That way the pharmacist can warn you and your provider if you take medicines that may cause problems when used together.
• Follow all instructions about how to take your medicine.
• Talk with your provider if side effects bother you.
• Never stop taking antidepressants without your provider's help. Stopping too fast may make depression come back. You could even make your condition worse. To stop antidepressants safely, you need to give your body time to get used to being without the medicine. Your provider can tell you the safest way to go off an antidepressant.

It sits within Mental Health and Behavior and Drug Therapy.

The lead U.S. institute for this subject is the National Institute of Mental Health.

Where to read more

Rather than paraphrase, we point you to the primary sources. Every link below is to a government health agency, a national institute or a recognised medical body — grouped by what you are trying to find out.

Medical subject headings

Clinicians and researchers index this subject under Antidepressive Agents. These are the terms to use when searching medical literature.

This page is built from the MedlinePlus health topic record for Antidepressants, a service of the U.S. National Library of Medicine (NLM), National Institutes of Health. Information is from MedlinePlus.gov. PocketsInfo is not affiliated with, and is not endorsed by, the NLM or the NIH. Retrieved 30 July 2026.