SSRIs or Selective Serotonin Reuptake Inhibitors

Mental health professional prescribes anti-depressant to male patient
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SSRIs, or selective serotonin reuptake inhibitors, are the most commonly prescribed antidepressants in the U.S. As their name suggests, SSRIs are used to treat depression.

SSRIs are believed to improve mood and treat depression by increasing serotonin levels in the brain.

List of SSRIs

Below is a list of SSRIs currently prescribed in the U.S.:

Luvox (fluvoxamine) is no longer available in the U.S. However, it is still available under the generic names, fluvoxamine and nefazodone.

FDA-Approved Uses

In addition to depression, SSRIs are FDA-approved to treat the following mental health conditions in adults, including:

SSRIs are also the first-line medication option for young people with depression and anxiety. The table below lists the FDA-approved uses for individual SSRIs.

  For Children For Adults
Celexa MDD
Lexapro MDD GAD, MDD
Trintellix MDD
Viibryd MDD

Off-Label Uses

Because of their ability to boost a person's mood, doctors prescribe SSRIs off-label to treat a variety of mood-related disorders.

Understanding Off-Label Use

“Off-label” use is when an FDA-approved drug is used in a way that has not been approved by the FDA. This can mean prescribing a drug for

  • A different age range: Treating children with a medication that has been approved for use in adults only
  • A different disease or condition: When a medication is used for a condition that it is not approved to treat
  • At a different dosage: When a medication is dosed differently than what has been approved

Off-label use does not imply illegal use. In fact, the practice is legal and quite common. According to a landmark study, one in five prescriptions is written for off-label use.

Not every SSRI is FDA-approved to treat every mood-related disorder. So although Paxil and Zoloft are the only medications approved by the FDA for PTSD, doctors may prescribe Prozac off-label.

The potential downside of prescribing SSRIs off-label is that doctors won't know about possible risks when they are used by people who are not depressed.

Bipolar Disorder

Mood stabilizers such as lithium are considered the first-line treatment for bipolar depression. If you're not responding to mood stabilizers or your depression is severe, your doctor may add on an SSRI. However, this is done with extreme caution because SSRIs can lead to more frequent mood episodes, known as rapid cycling.

Precautions and Contraindications

SSRIs are not for everyone and must be used with caution in certain individuals.

Pregnant and Breastfeeding Women

Hundreds of studies have looked at SSRI exposure and birth defects. Overall, SSRIs are generally considered safe to use during pregnancy. But they are not without risk.

  • Birth defects: SSRI use during pregnancy may increase the risk of abdominal, heart, and lung birth defects.
  • Blood loss after childbirth: Some studies have reported a slightly higher risk of postpartum hemorrhage among women on SSRIs.
  • Miscarriage and premature birth: Pregnant women on antidepressants are at increased risk for a number of complications, including miscarriage and premature delivery.
  • Psychiatric disorders in children: Children of mothers who used antidepressants before and during pregnancy have a higher risk of developing a psychiatric disorder. However, this association may be attributable to the severity of the mother’s underlying condition.
  • Withdrawal symptoms in newborns: Newborns exposed to SSRIs in the last trimester may experience withdrawal symptoms. The most common withdrawal symptoms are tremors, disturbed sleep, and high-pitched crying.

It's also possible that SSRIs can be passed to your baby through your breastmilk. However, these levels are usually low enough that they won't have an adverse effects on nursing infants.

Letting depression go untreated can also have a negative impact on a pregnancy. Remember to always weigh the risks of SSRI treatment to the risks of untreated depression.


In 2004, the FDA issued a black box warning—the agency's strictest warning—that young people (up to age 25) taking antidepressants might experience increased suicidal thoughts and behaviors.

The warning also says that children and adolescents taking SSRIs should be carefully watched for sudden changes in their mood or actions, such as:

  • Aggressive or hostile behavior
  • Extreme increase in movement and talking
  • Making suicidal statements
  • Trouble sleeping
  • Withdrawal from friends and family

If you see any of these signs in your child, particularly if they are new or noticeably worse than before, be sure to talk to your doctor as soon as possible.

If your child is having suicidal thoughts, contact the National Suicide Prevention Lifeline at 1-800-273-8255 for support and assistance from a trained counselor. If you or a loved one are in immediate danger, call 911.

For more mental health resources, see our National Helpline Database.

Side Effects

As a whole, SSRIs are considered the most effective antidepressants with the fewest side effects. The majority of people who take them experience at least one side effect. Most of them are minor and usually go away on their own over time.

Common side effects of most SSRIs include:

  • Diarrhea
  • Drowsiness
  • Dry mouth
  • Headache
  • Increased sweating
  • Insomnia
  • Nausea and vomiting
  • Sexual dysfunction (ejaculation failure and decreased libido)
  • Weight gain

Ask your doctor to explain all the known side effects of your chosen SSRI. If you're experiencing one or more of these side effects, talk to your doctor. They may be able to suggest ways to lessen them.

Serotonin Syndrome

Having too much serotonin in your blood can cause a serious but uncommon condition called serotonin syndrome. Serotonin syndrome is triggered by taking too many antidepressants or taking them with certain supplements.

Symptoms of serotonin syndrome include:

  • Autonomic effects: Abnormally fast heart rate, hypertension, hyperthermia, shivering, sweating
  • Mental status effects: Confusion, delirium, excitement, restlessness, and hallucinations.
  • Neuromuscular effects: Muscle twitching, tremor, and increased reflexes.

Before starting any medication, it is important that you discuss all the medications you're taking with your doctor to avoid this potentially life-threatening condition.

What Happens When I Stop An SSRI?

Here is a look at the causes and symptoms of SSRI Discontinuation Syndrome, the uncomfortable reaction some people have to cut down or quit certain types of antidepressants.

Here are tips for both pill and capsule handling to ease the effects of lowering your dosage or discontinuing an SSRI antidepressant medication—when a too-abrupt transition could cause troubling symptoms.

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