What's the Difference?

Effexor pills, which are used to treat depression and other ailments.
Effexor pills, which are used to treat depression and other ailments. Joe Raedle/Getty Images

There is some confusion about the terms SSNRI and SNRI. SSNRI is rarely used anymore in favor of SNRI.

The Confusion in Terms

SNRI stands for both selective serotonin-norepinephrine reuptake inhibitor and serotonin-norepinephrine reuptake inhibitor. SSNRI stands only for selective serotonin-norepinephrine reuptake inhibitor, but is used interchangeably with SNRI now and rarely used alone. Then there are also selective norepinephrine reuptake inhibitors, commonly referred to as NRIs.

Selective Serotonin-Norepinephrine Reuptake Inhibitors and Serotonin-Norepinephrine Reuptake Inhibitors (SSNRIs or SNRIs)

The drugs that inhibit reuptake of both the neurotransmitters serotonin and norepinephrine to boost mood, and are commonly called SNRIs, but also include SSNRIs, are:

Side Effects of SNRIs

Common side effects include:

  • Dizziness
  • Sweating
  • Dry mouth
  • Upset stomach
  • Fatigue
  • Headache
  • Constipation
  • Sexual issues
  • Anxiety
  • Difficulty sleeping
  • Appetite loss

Selective Norpinephrine Reuptake Inhibitors (NRIs)

NRIs are used for ailments like attention deficit/hyperactivity disorder (ADHD), depression and anxiety.

Common medications include:

  • Strattera (atomoxetine) is mainly used to treat ADHD.
  • Ludiomil (maprotiline) is used for depression and anxiety.

Side Effects of NRIs

Typical side effects of NRIs include:

  • Skin redness
  • Hives
  • Itching
  • Rash
  • Heartbeat irregularity
  • Sexual issues
  • Fatigue or weakness
  • Blurred vision
  • Constipation
  • Light-sensitive skin
  • Upset stomach

Other Medications Used for Bipolar Disorder

Antidepressants such as SNRIs are sometimes appropriate for use in your treatment plan if you have bipolar disorder. Since they can trigger a manic episode, however, if you have bipolar I disorder, you will likely need a mood stablizer or an antipsychotic too.

Mood Stabilizers

Like the name describes, these medications help keep your mood stable and help prevent you from having manic or hypomanic episodes. A few of the medications used as mood stabilizers are actually anti-convulsants used for people with epilepsy too. Some common mood stabilizers are:

  • Lithium
  • Depakote (divalproex sodium)
  • Tegretol (carbamazepine)
  • Lamictal (lamotrigine)

Possible side effects of mood stabilizers are feeling thirsty, rash, upset stomach, seizures, slurring of speech, swelling, tremor, vision changes, irregular heartbeat, having to urinate often, hallucinations and blackouts.


One of these medications may be added or replaced in your treatment regimen if you are still having problems with your mood being either too low or too high.

Typical anti-psychotics include:

  • Risperdal (risperidone)
  • Geodon (ziprasidone)
  • Zyprexa (olanzapine )
  • Abilify (aripiprazole)
  • Latuda (lurasidone )

Side effects of anti-psychotics may include low blood pressure, blurry vision, dizziness, gaining weight, seizures, drowsiness, dry mouth, vomiting, tics or tremors. low white blood cell count and upset stomach.

Anti-Anxiety Medication

If you are having trouble with anxiety and/or your sleep, your mental health professional may prescribe you an anti-anxiety medication called a benzodiazepine to help. Common ones include:

  • Xanax (alprazolam)
  • Klonopin (clonazepam)
  • Valium (deazepam)
  • Ativan (lorazepam)

Side effects of anti-anxiety medications can include confusion, drowsiness, weakness, breathing difficulties, slurred speech and coordination problems. They are often taken before bed to help you sleep, however, so you may not notice these effects.


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"Duloxetine (Cymbalta)." National Alliance on Mental Illness (2013).

"Venlafaxine (Effexor)." National Alliance on Mental Illness (2013).

"Levomilnacipran (Fetzima)." National Alliance on Mental Illness (2013).

"Milnacipran (Oral Route)." Mayo Clinic (2016).

"Serotonin and norepinephrine reuptake inhibitors." Mayo Clinic (2013).

"Maprotiline." MedLine Plus, U.S. National Library of Medicine (2010).

"Mental Health Medications." National Institute of Mental Health (2016).

"Bipolar Disorder." Mayo Clinic (2015).

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