Lexapro vs. Prozac: Comparison of Effectiveness

January 20, 2021

Mental health conditions like major depressive disorder and anxiety disorders are extremely common in the United States, affecting millions of people of all ages. 

Since the 1980s, a new class of antidepressant medications called selective serotonin reuptake inhibitors (SSRIs) became available for the treatment of a number of different mental health conditions. Among this new class of drugs were Lexapro and Prozac, two of the most popular antidepressant medications currently on the market. 

Lexapro, which is sold under the generic name escitalopram, and Prozac, sold under the generic name fluoxetine, are both effective at treating mental health conditions. However, when it comes to Lexapro vs. Prozac, is one better?

Drug Class

Lexapro and Prozac both belong to a class of drugs called selective serotonin reuptake inhibitors (SSRIs). 

This drug class is a newer generation of antidepressants that works by blocking the reuptake of serotonin, a neurotransmitter, in the brain. As a result, serotonin levels remain elevated, helping to improve and stabilize mood. 

Lexapro and Prozac can help minimize the physical symptoms of depression, allowing people to regain interest in hobbies that they used to enjoy.

Conditions Treated

Major Depressive Disorder

Both Lexapro and Prozac are used for the treatment of major depressive disorder, also known as clinical depression. 

This mental health condition is indicated by intense feelings of sadness that persist for an extended period of time, i.e. at least two weeks or more. 

Major depressive disorder causes a number of symptoms to occur, including mental, physical, and emotional symptoms. It is common for people experiencing major depression to experience changes in appetite, such as eating much more or much less than usual, or changes in sleep, such as insomnia or sleeping more than usual. People with major depressive disorder commonly lose interest in doing activities that they once enjoyed or have trouble performing everyday activities. They may also have suicidal thoughts and tendencies. 

Symptoms of major depressive disorder include:

  • Feelings of worthlessness, guilt, hopelessness, or helplessness
  • Lost of interest in activities you used to enjoy
  • Feelings of moving or thinking in slow motion
  • Sleeping and eating more or less than usual
  • Feeling sad, empty, or tearful
  • Difficulty concentrating
  • Low energy
  • Nervous energy
  • Suicidal thoughts or behaviors

Generalized Anxiety Disorder

In addition to major depressive disorder, Lexapro can also be used for the treatment of generalized anxiety disorder, or GAD. While it is normal for people to experience feelings of anxiety from time to time, anxiety disorders occur when a person’s anxiety becomes severe, lasts for six months or more, and interferes with a person’s quality of life. Symptoms of generalized anxiety disorder can include restlessness, panic attacks, difficulty falling asleep,  an increased heart rate, rapid breathing, and trouble concentrating. 

Other Conditions

In addition to major depressive disorder, Prozac is also used for the treatment of obsessive-compulsive disorder, panic disorder, bulimia nervosa, and premenstrual dysphoric disorder. 

Obsessive-compulsive disorder, or OCD, is characterized by obsessive, worrisome thoughts that cause anxiety, paired with compulsive behaviors that are intended to relieve the feelings of anxiety. 

Panic disorder manifests as intense and repeated episodes of overwhelming fear, called panic attacks, that cause physical symptoms like heart palpitations, shortness of breath, and chest pain. 

Bulimia nervosa is a type of eating disorder characterized by binging, or consuming a large amount of food in a short period of time, followed by purging, or eliminating the food to prevent weight gain. 

Common purging behaviors include laxative abuse, induced vomiting, or excessive exercise. 

Premenstrual dysphoric disorder, commonly referred to as PMDD, is a type of mood disorder that occurs several days prior to menstruation and is characterized by extreme feelings of depression, tension, and irritability.

Effectiveness

Several studies have examined the differences in effectiveness between Lexapro and Prozac. Overall, a review of the studies found that Lexapro and Prozac are equally effective when treating major depressive disorder, the only condition in which both medications are used as treatment.

However, antidepressants work differently for everyone, so some people will experience better results when taking Lexapro, or vice versa.

No matter which medication your doctor prescribes, expect to give the drug about two to four weeks to start working. SSRIs like Lexapro and Prozac take time to affect your brain chemistry, and patients may not experience the full effects of either drug for about four weeks.

Side Effects

When considering side effects, those associated with Lexapro are generally more mild than the side effects associated with Prozac. This is because the half life of Lexapro is much shorter than the half life of Prozac, which means it is processed through the body more quickly, limiting the incidence of side effects. 

Lexapro

Although the side effects associated with Lexapro are generally less severe than those associated with Prozac, some side effects do still exist. The side effects of Lexapro are slightly different for children and adults. 

Common side effects of Lexapro use in adults include:

  • Nausea
  • Unusual changes in sex drive and other sexual issues like erectile dysfunction and premature ejaculation 
  • Dry mouth
  • Infection
  • Sleepiness
  • Shaking
  • Weakness
  • Weight gain
  • Anxiety
  • Loss of appetite
  • Constipation
  • Dizziness
  • Trouble sleeping
  • Sweating
  • Yawning

Children and adolescents may experience the same possible side effects listed above for adults, but may also experience the following:

  • Increased thirst
  • Abnormal increase in muscle movement or agitation
  • Nosebleeds
  • Heavy menstrual periods
  • Trouble urinating
  • Slowed growth and weight change or weight loss

Rare but serious side effects associated with Lexapro include:

  • Severe allergic reaction, as evidenced by:
    • Severe rash, hives, or blisters that may be accompanied by fever or joint pain
    • Breathing trouble
    • Swelling of the face, tongue, eyes, or mouth
  • Seizures or convulsions
  • Low salt levels, as evidenced by:
    • Headache
    • Trouble concentrating
    • Confusion
    • Thinking or memory problems
    • Weakness
    • Seizures
    • Irregular heartbeat
    • Unsteadiness that can lead to falls
  • Serotonin syndrome, as evidenced by:
    • Shivering
    • Severe muscular tightness
    • Fever
    • Seizures
    • Diarrhea
    • Confusion
    • Death
  • Manic episodes, as evidenced by:
    • Greatly increased energy
    • Talking quickly or more than normal
    • Severe sleeping trouble
    • Racing thoughts
    • Unusually grand ideas
    • Reckless behavior
    • Excessive happiness or irritability
  • Vision problems, as evidenced by:
    • Eye pain
    • Changes in your vision
    • Swelling or redness in or around your eye

If you experience any of these side effects, seek medical attention immediately. 

Prozac

Side effects associated with Prozac generally fall into two categories: common and rare but serious. 

Common side effects associated with Prozac include:

  • Headache
  • Fatigue
  • Weight loss
  • Drowsiness and tiredness
  • Increased sweating
  • Feeling nervous
  • Increased bruising or minor skin rashes
  • Nausea
  • Diarrhea
  • Dry Mouth or sore throat 
  • Restlessness
  • Difficulty sleeping (insomnia)
  • Decreased libido or sex drive
  • Sexual dysfunction, such as difficulty with orgasm or ejaculatory delay

Rare but serious side effects associated with Prozac include:

  • Low sodium blood levels, as evidenced by:
    • Headache
    • Difficulty remembering
    • Weakness
    • Difficulty concentrating
  • Teeth grinding
  • Angle-closure glaucoma, as evidenced by:
    • Eye pain
    • Changes in vision
    • Swelling or redness in or around the eye
  • Serotonin syndrome, as evidenced by:
    • Shivering
    • Fever
    • Seizures
    • Diarrhea
    • Confusion
    • Severe muscular tightness
    • Death
  • QT prolongation and ventricular arrhythmia including changes in the electrical activity of your heart

Drug Interactions

Both Lexapro and Prozac have the potential to cause potentially dangerous reactions when interacting with other medications. 

Monoamine oxidase inhibitors, or MAOIs, should not be used within 14 days of using Lexapro or Prozac, as the drugs can interact and cause serotonin syndrome. Serotonin syndrome is a serious medical condition that is caused by a buildup of serotonin in the brain. Common symptoms of serotonin syndrome include shivering, fever, seizures, diarrhea, confusion, severe muscular tightness, and death. 

Other medications that affect the amount of serotonin in the body, including other antidepressants and triptans used to treat migraines, can also interact with Lexapro and Prozac and cause serotonin syndrome. This can also occur with the cough suppressant dextromethorphan, which is commonly found in Robitussin-DM.

In addition to interacting with drugs that influence the amount of serotonin in the brain, Lexapro and Prozac can also interact with macrolide antibiotics, non-steroidal anti-inflammatory drugs (NSAIDs), painkillers like tramadol, and alcohol. 

Summary

Lexapro and Prozac are both equally effective in the treatment of mental health conditions like major depressive disorder, but the drugs will work differently for different patients. 

Lexapro and Prozac are both used for the treatment of major depressive disorder, while Lexapro is also prescribed for the treatment of generalized anxiety disorder. Prozac is also prescribed for the treatment of obsessive-compulsive disorder, panic disorder, bulimia nervosa, and premenstrual dysphoric disorder. 

If you are considering Lexapro or Prozac for the treatment of a mental health condition, YANA can help connect you with a licensed physician that can talk to you about your symptoms, make a diagnosis, and prescribe the medication that is right for you, all from the comfort of your own home and at an affordable price. 

Sources:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4164382/

https://www.healthline.com/health/depression/prozac-lexapro

https://www.healthline.com/health/depression/lexapro-side-effects