Medical Disclaimer
The medicines listed on this website are only there to give you knowledge. Just because they are on the list doesn’t mean that anyone will be given them; in the end, treatment decisions are up to the healthcare workers. The medicines on this list are not all of them. Doctors may recommend other drugs, even ones that don’t contain stimulants, depending on the patient’s specific health needs and circumstances. Read more
Two popular kinds of antidepressants used for different mental health issues are SNRIs (selective serotonin-norepinephrine reuptake inhibitors) and SSRIs (selective serotonin reuptake inhibitors). They are a part of the new generation of antidepressants, which improve mental health noticeably and are safer and less likely to cause adverse effects than the older ones.
In spite of their many similarities, they differ significantly in terms of how they function, possible applications, adverse effects, and medication interactions. Which antidepressant class—SSRI or SNRI—might be better for you will be discussed in more depth with your doctor after reading this page, which also provides answers to frequently asked questions regarding these drugs.
SSRI vs. SNRI: Synopsis
The new era of antidepressant drugs began with the introduction of SNRIs into the market in 1993, while the FDA approved SSRIs in 1987. These drugs were initially created to treat depression, but further investigation[1*] has indicated that they can also be used to treat a number of other mental and physical illnesses. The following is a list of drugs that fall under each class:
| SSRIs | SNRIs |
| Lexapro (escitalopram) | Pristiq (desvenlafaxine) |
| Citalopram, also known as Celexa | Cymbalta (duloxetine) |
| Prozac, or fluoxetine | Effexor (venlafaxine) |
| Acetaminophen (Paxil, Pexeva) | Fetsima Levomilnacipran |
| Zoloft, or sertraline | Savella, or Milnacipran |
| Fluvoxamine, also known as Luvox | |
| Vilazodone (Viibryd) |
These new antidepressants are generally more tolerable, have a safer profile, and require less dosage adjustments. Long-term quality of life is enhanced by them as they lessen the symptoms of a variety of psychological issues, such as PTSD, OCD, depression, anxiety disorders, and phobias.
SNRI vs. SSRI: Distinctions and Parallels
Their modes of action are where SNRIs and SSRIs diverge most. SSRIs function by postponing the brain’s nerve cells’ intake of serotonin. Patients have reduced depression symptoms as a result of the brain having access to more serotonin for a longer period of time.
SNRIs apply the concept of working with a single, significant modification. They not only prevent the brain from absorbing serotonin, but they also prevent norepinephrine from being reabsorbed.
It is crucial to discuss here how serotonin regulates mood. Serotonin is one of the neurochemicals essential to happiness’s biological functioning.[2*] Our brain releases dopamine and serotonin, among other “happy hormones and chemicals,” whenever we engage in enjoyable activities. Antidepressants (SSRIs and SNRIs) are thought to balance these “happy hormones” in the brain because it is suspected that depression is caused by a deficiency of serotonin.
Norepinephrine, on the other hand, is essential for the body’s fight-or-flight response in any situation. The body releases more norepinephrine when someone is under a lot of stress for any cause, such as a test, job interview, etc. It affects a person’s mood[3*], motivation, reasoning, sleep, and reasoning. Therefore, theories suggest that this bodily imbalance may also trigger depression.
In addition to these functional distinctions, SSRIs and SNRIs share several other characteristics, such as safety, effectiveness, and treatment duration. The table below provides a summary of the key differences between SNRIs and SSRIs:
| Characteristic | Serotonin reuptake inhibitors, or SSRIs | Serotonin-norepinephrine reuptake inhibitors, or SNRIs |
Variations | ||
| Method of Action | focuses on serotonin receptors | It targets the receptors for serotonin and norepinephrine. |
| FDA Approved | 1987 | 1993 |
| Half-life | comparatively long when compared to other depression medications | brief in comparison to other antidepressants |
Comparabilities | ||
| Security | Comparatively safer than earlier generation antidepressants | |
| Effectiveness | equivalent to earlier antidepressants | |
| Length of Treatment | Long (generally, six months or more, depending on the state of the patient) | |
| Dosage | Depending on the particular drug and the ailment being treated | |
| Price | erratic and dependent on the particular drug | |
| Protection From Insurance | Depending on the insurance company | |
| Online prescription | accessible via authorized internet platforms | |
SNRI vs. SSRI: Applications
People often use both SNRIs and SSRIs to treat various medical issues as well as a number of mental health disorders. We administer medications from these antidepressant classes for both off-label and alternative label uses.
Below is a summary of the numerous conditions that SSRIs and SNRIs treat.
FDA-Approved Applications
Depression
The FDA recommends using all SSRIs for treating depression, with the exception of fluvoxamine, often known as Luvox, which is used to treat OCD. Sertraline and fluoxetine are two SSRIs that reduce PMDD symptoms in women. PMDD is related to the menstrual cycle.
Currently, four SNRI medications are licensed to treat depression; the only one that isn’t is milnacipran (Savella), which is approved in the US to treat fibromyalgia. These drugs often treat moderate to severe cases of depression, as they are less effective in mild depression cases.
Anxiety Disorder
The FDA has authorized SNRIs and SSRIs for the treatment of panic disorders with or without agoraphobia. The treatment of panic disorders involves the prescription of three medications from the SSRI family: sertraline, fluoxetine, and paroxetine. These medications are particularly beneficial when panic disorder and depression coexist.
Compulsive-obsessive Disorder
An SSRI called fluvoxamine (Luvox) has a license specifically to treat OCD in humans. Other SSRIs, such as paroxetine, sertraline, and fluoxetine, are also used to treat OCD in addition to fluvoxamine. The dosages used to treat OCD are usually greater than those used to treat depression, and it takes a while for OCD sufferers to have any positive results. By contrast, the FDA has not authorized any SNRI for the treatment of OCD. However, we administer them off-label for this ailment.
Anxiety Disorders: Social and Generalized
Certain SSRIs and SNRIs treat specific phobias as well as generalized and social anxiety disorders. The diagnosis and severity of the patient’s symptoms determine the medication that is best. For generalized anxiety disorder (GAD), the FDA has authorized paroxetine, escitalopram, duloxetine, and venlafaxine; for social anxiety, the recommended medications are sertraline, paroxetine, and extended-release venlafaxine.
Disorder of Posttraumatic Stress
The first-choice method of treating PTSD is therapy. Medication, however, could also be necessary to control symptoms. Doctors often advise SSRIs for this reason since they are effective at managing the intrusive and avoidant symptoms of PTSD.
Nervous bulimia
SSRIs are also used to treat anorexia and bulimia, two obsessive illnesses linked to eating behaviors. We specifically use fluoxetine for this. Psychotherapy is the preferred treatment for these disorders, but SSRIs may lessen the binge eating and vomiting associated with bulimia.
Pain in Neuropathic Nerves
In addition to treating mental health issues, these drugs also treat physical disorders. The FDA recommends SNRIs to treat various body nerve problems. Duloxetine[4*] has been licensed by the FDA to treat fibromyalgia (chronic muscle pain) and neuropathic pain linked to diabetes.
Off-Label Applications
When a doctor prescribes a drug that is authorized for one illness but has not yet received FDA approval for another ailment, the practice is known as off-label usage. SSRIs and SNRIs treat the following medical conditions off-label.
Early Fertilization
Males who ejaculate too soon often receive SSRIs off-label due to their anorgasmic effects. Sertraline and fluoxetine are often used for this purpose.
headaches
People who also have depression often use SSRIs to treat long-lasting migraine headaches.
Autism
Certain SSRIs are used to treat the symptoms of autism spectrum disorders.
Urinary Incontinence Stress
The FDA is now reviewing duloxetine’s application for clearance to treat stress incontinence, which is the most prevalent kind of pee incontinence (inability to retain urine) in women.
| Condition | FDA-Sanctioned Application | Off-label Use | ||
|---|---|---|---|---|
| SSRIs | SNRIs | SSRIs | SNRIs | |
| Major depressive disorder | ✅ | ✅ | ❌ | ❌ |
| Obsessive-Compulsive Disorder (OCD) | ✅ | ❌ | ❌ | ✅ |
| Generalized Anxiety Disorders (GAD) | ✅ | ✅ | ❌ | ❌ |
| Panic Disorder | ✅ | ✅ | ❌ | ❌ |
| Social anxiety disorder (SAD) | ✅ | ✅ | ❌ | ❌ |
| Premenstrual dysphoric disorder (PMDD) | ✅ | ❌ | ❌ | ✅ |
| Post-traumatic stress disorder (PTSD) | ✅ | ❌ | ❌ | ✅ |
| Bulimia nervosa | ✅ | ❌ | ❌ | ✅ |
| Bipolar Disorder | ✅ | ❌ | ❌ | ✅ |
| Diabetic neuropathy | ❌ | ✅ | ❌ | ❌ |
| Fibromyalgia | ❌ | ❌ | ❌ | ✅ |
| Premature ejaculation | ❌ | ❌ | ✅ | ❌ |
| ADHD | ❌ | |||
| Autism | ❌ | ❌ | ✅ | ❌ |
SNRI vs. SSRI: Interactions and Side Effects
Both SSRIs and SNRIs experience similar negative effects, although each individual experiences these side effects differently. The following are the most typical SSRI and SNRI adverse effects:
The following are the most typical SSRI and SNRI adverse effects:
- Lightheadedness
- Hazed vision
- Parched lips
- Dysfunctional relationships
- Digestive issues, such as diarrhea or constipation
- Issues with rest
- Vertigo and queasiness
- Variations in weight (increase or reduction)
The details of these drugs’ more severe adverse effects are provided below.
Impacts on the Heart
SSRIs and SNRIs have the potential to lengthen QT intervals, which may result in irregular heart rhythms. Individuals who use antipsychotic drugs in addition to antidepressants are particularly at risk. Citalopram has the greatest effect on the QT interval among these drug types.
Headaches
A study[5*] found that SSRIs and SNRIs may increase the frequency of headaches in individuals.
Convulsions
Seizures[6*] are an uncommon adverse effect that may occur in individuals receiving higher dosages of SSRIs and SNRIs.
Impacts on Blood
SSRIs and SNRIs cause certain blood-related issues, such as the inhibition of platelet aggregation. These medications may increase the risk of bleeding, especially in cases of severe injuries. Therefore, we advise additional vigilance when combining these drugs with NSAIDs like ibuprofen or blood thinners like aspirin.
Impacts on Electrolytes and Blood Sugar
Diabetes patients’ blood sugar levels may be lowered by these medications. Therefore, individuals who have problems with their blood sugar should take these drugs with caution. Additionally, they may have an impact on the body’s salt and other electrolyte levels, which might lead to fatigue.
Impacts on Hormones
Both men and women who use SSRIs may experience an increase in prolactin hormone levels, primarily linked to breast growth and milk production. Stopping therapy can reverse any breast alterations that may occur while taking these drugs.
Beyond-Paradoxical Impacts
Patients with akathisia (the inability to stay still), torticollis (twisting of the neck), dystonia (uncontrolled movements), bradykinesia (slow movements), and opisthotonos (muscle spasms) might experience movement problems due to taking SSRIs.
Serotonin Syndrome
Using SSRIs or SNRIs with other antidepressants like lithium, l-tryptophan, or MAOIs can lead to dangerously high serotonin levels in the body. This condition is known as serotonin syndrome[7*] and is characterized by a wide range of symptoms.
- Anxiety
- Having diarrhea
- Extreme anxiety
- Uncontrollable bodily motions
- elevated temperature
- Convulsions
- Coma with Delirium
- collapse of the heart
Effects of Acute Withdrawal
Abrupt cessation of these medications may result in withdrawal symptoms. The following symptoms may manifest when abruptly stopping these drugs:
- Fatigue
- Lightheadedness
- A headache
- Fear
- Sleeplessness
- Rebound depression
- Feeling numb
- Issues with concentration
*Black Box Alert. Fluvoxamine, paroxetine, fluoxetine, sertraline, citalopram, and venlafaxine are among the SSRIs and SNRIs that the FDA has listed as having serious side effects. This warning is given to SSRIs and SNRIs because they have the potential to make children, adolescents, and young adults up to the age of 24 consider suicide. Therefore, we closely monitor these age groups during the initial stages of treatment.
The table below lists the common and dangerous side effects of SSRIs and SNRIs.
| Common SNRI and SSRI side effects | Serious SNRI and SSRI side effects |
|
|
Relationships between Medications.
It is usually safe to combine SSRIs and SNRIs with other prescription drugs. However, before starting antidepressant therapy, you must inform your doctor about all of the drugs you are taking since there are some interactions to be cautious of.
Similar drug interactions occur between SNRIs and SSRIs; the most frequent ones are included in the table below:
| Medicine | Class of Drugs | Potential Interaction between SNRIs and SSRIs |
phenelzine Isocarboxazid | MAOIs | Serotonin Syndrome |
| Lithium-based | agents that are antimanic | Serotonin Syndrome |
| Tryptophan L- | α-amino acid | Serotonin Syndrome |
Amitriptyl Nottriptyline | TCAs | TCA toxicity in therapeutic settings |
Codeine Oxycodone Hydrocodone | Opioids | Reduced ability to effectively manage discomfort |
| Tamoxifen | Anti-estrogens without steroids | Diminished efficacy |
Ibuprofen Naproxen Diclofenac | NSAIDs | elevated risk of stomach hemorrhage |
| Clozapine | Unusual antipsychotics | elevated seizure risk |
Warfarin Apixaban | Anticoagulants | increased chance of bleeding |
See a physician or pharmacist for information on all the potential combinations.
Final Thought
Based on the aforementioned data, it can be concluded that, apart from a few small variations, SSRIs and SNRIs are essentially comparable in terms of their applications, tolerability, effectiveness, and safety profile. However, only a licensed medical professional can determine which drug is appropriate for your situation after reviewing all of your medical records.
FAQs on SNRI vs. SSRI
Which is better: SSRIs or SNRIs?
Several studies[8*] have been done to assess the effectiveness of SNRIs and SSRIs; however, no clinically significant difference has been seen between the two. Compared to SSRIs, which only target serotonin receptors in the brain, SNRIs target both noradrenaline and serotonin receptors, giving them a modest advantage in their mode of action. However, the doctor’s judgment, which is based on the whole evaluation, together with the patient’s symptoms and diagnosis, will determine which drug is prescribed.
Can you take SSRIs and SNRIs together for faster results?
While both SSRIs and SNRIs are generally safe drugs, there is no proof that taking them together would help you get effects more quickly. Furthermore, to prevent any major side effects, it is imperative that you take these prescriptions exactly as prescribed by your doctor.
Is it possible to switch from SNRIs to SSRIs?
The answer is that switching from SNRIs to SSRIs is doable. But your doctor must take into account a number of factors before altering your treatment plan in this way, including your medication and medical history, how you respond to therapy, any adverse effects, etc. Your doctor may only convert your medication from SNRIs to SSRIs after conducting a thorough examination and ruling out any warning signs.
Which is the safer medication: SSRI or SNRI?
There are similar adverse effects seen by both SSRIs and SNRIs. There is no medical proof that one of them is more secure than the other. Your medical condition, medical history, and other variables, such as age and genetics, will all influence the drug that is prescribed for your therapy.
Is it safe to use SSRIs or SNRIs during pregnancy?
It is safe to utilize the majority of SSRIs and SNRIs while pregnant. However, avoid paroxetine (SSRI) during pregnancy as it increases the risk of congenital malformations, particularly cardiac problems.
How to get SSRI or SNRI prescribed?
You must first get an evaluation by a physician to see if you need any of these drugs before you can receive a prescription for SSRIs or SNRIs. This procedure has been greatly simplified by telemedicine. Medication may be given to you from the convenience of your home; this is an easy and affordable procedure that saves you from having to go to the doctor.
