Celexa vs. Zoloft: Differences, similarities, and which is better for you

Drug overview & main differences | Conditions treated | Efficacy | Insurance coverage and cost comparison | Side effects | Drug interactions | Warnings | FAQ

Celexa and Zoloft are two prescription medications used in the treatment of major depression disorder (MDD), sometimes simply referred to as depression. Depression is one of the most prevalent mental health conditions in the United States, and it is characterized by prolonged (2 weeks or more) feelings of low mood and decreased energy levels. Patients may not find joy in things they enjoyed previously. The Anxiety and Depression Association of America (ADAA) estimate that over 20% of adults in the United States will develop MDD at some point in their life. Mental health conditions are not always adequately treated or treated at all. Many factors contribute to that trend including an inability to recognize signs and symptoms and stereotypes about the conditions. Celexa (citalopram) and Zoloft (sertraline) are two antidepressant medications that treat the symptoms of depression.

What are the main differences between Celexa and Zoloft?

Celexa is a prescription medication indicated in the treatment of depression. It belongs to a class of drugs known as selective serotonin reuptake inhibitors (SSRIs) and is available generically as citalopram. Neurotransmitters like serotonin move between neurons via selective pumps. Celexa blocks the reuptake of serotonin by the pump. By blocking serotonin reuptake by the transport pump, the drug is effectively leaving more free serotonin in the neuron synapse. Higher levels of serotonin are associated with improved mood and energy levels. The active ingredient, citalopram, has two isomers in its formulation, R-citalopram and S-citalopram. The S-isomer is primarily responsible for the serotonin blockade that makes citalopram effective. Another SSRI, Lexapro (escitalopram), is composed only of the S-isomer of citalopram.

Celexa is available in an oral tablet formulation in strengths of 10 mg, 20 mg, and 40 mg. It is also available in an oral liquid solution in concentrations of 10 mg/5 ml and 20 mg/5 ml.

Zoloft  (sertraline) is also a prescription medication in the SSRI class indicated in the treatment of depression. Zoloft also works by blocking the reuptake of only serotonin at the neuronal synapse. Other SSRIs you may be familiar with include Prozac (fluoxetine), and Paxil (paroxetine). 

Zoloft is available as an oral tablet in strengths of 25 mg, 50 mg, and 100mg. It is also available in an oral concentrated solution that is 20 mg/ ml. 

Conditions treated by Celexa and Zoloft

Celexa and Zoloft are each Food and Drug Administration (FDA) approved to treat major depressive disorder. They also each have some unique indications for use. Zoloft is approved by the FDA) in the treatment of social anxiety disorder and obsessive-compulsive disorder (OCD). Both Celexa and Zoloft are used off-label in generalized anxiety disorder (GAD), panic disorder, and premature ejaculation.  

This table of indications is for informational purposes only and is not meant to be official medical advice. Please visit your healthcare professional to determine which treatment is best for your condition.

Is Celexa or Zoloft more effective?

Celexa and Zoloft have been studied head to head in clinical trials. A double-blind, randomized trial for a six-week period found both drugs to be effective at treating depression. They also were both tolerated well. However, Celexa showed earlier signs of symptom improvement, providing relief of depressive symptoms more quickly than Zoloft. The delay in symptom relief can be a factor in the early discontinuation of therapy because patients don’t realize a benefit fast enough. An earlier onset of relief can be a significant contributing factor to medication compliance. Your psychiatry professional will help decide what is right for you.

Coverage and cost comparison of Celexa vs. Zoloft

Celexa is a prescription medication that is covered by both commercial and Medicare drug insurance plans. The out-of-pocket price of Celexa can be more than $400 for a one-month supply. With a coupon from SingleCare, you could obtain the generic medication for as low as $4.

Zoloft is also a prescription drug that is generally covered by both Medicare and commercial drug plans. The out-of-pocket price of brand-name Zoloft may be more than $500, but with a coupon from SingleCare, you could pay less than $10 for the generic form.

Common side effects of Celexa vs. Zoloft

Celexa and Zoloft each work by the same mechanism to increase serotonin, and their adverse event profiles are similar as well. Both medications are linked to instances of dry mouth, nausea, vomiting, diarrhea, and sweating. Somnolence, or excessive drowsiness, is also a potential side effect the two antidepressants share. 

There are some differences that may be important for clinicians to consider. Celexa is not linked to constipation or decreased appetite, but Zoloft is. This would be an important consideration in patients with preexisting treatments or disorders which may also affect the gastrointestinal function of your body or appetite. Decreased libido (sex drive) is slightly more common with Zoloft and is a concern that should be addressed prior to starting therapy with either drug.

Source: DailyMed (Celexa) Dailymed (Zoloft)

Drug interactions of Celexa vs. Zoloft

Due to their chemical similarities, Celexa and Zoloft cause similar concerns for drug interactions. Both drugs are metabolized through the cytochrome P450 enzyme system. Celexa and Zoloft may increase the serum concentrations of antipsychotics, such as aripiprazole, through their inhibition of CYP2D6. If the use of these two drugs together is necessary, patients should be monitored for the effects of higher concentrations of the antipsychotics. In some patients, a dose decrease of the antipsychotic may be necessary.

Celexa and Zoloft have the potential to cause serotonin syndrome when mixed with other drugs with serotonergic actions. Serotonin syndrome is the result of abnormally high levels of free serotonin and can result in agitation, dizziness, and increased heart rate. Drugs such as the migraine medication almotriptan, tramadol for pain, or St. John’s Wort supplement may cause this interaction.

Zoloft may cause a specific type of cardiac arrhythmia known as a prolonged QTc interval when taken with certain classes of medication.  It is important that your healthcare professional and pharmacist have a complete list of medications you are taking in order to appropriately screen for potential interactions.

The following list is not intended to be a complete list of drug interactions. Your doctor or pharmacist can provide a complete list.

Warnings of Celexa and Zoloft

You should not take Celexa or Zoloft if you have ever had allergic reactions to any other SSRIs.

Celexa and Zoloft will not start resolving depressive symptoms immediately. Typically, changes in symptoms take a minimum of two weeks to observe, with most patients needing at least four to six weeks to see if the drug is having an impact on their symptoms.

Adults and children who suffer from MDD are more likely to suffer from suicidal ideation. This can get worse if MDD is not adequately treated, or not treated at all. Some studies have shown that antidepressant drugs, including SSRIs, can increase suicidal thoughts in children and young adults. All patients taking SSRIs should be monitored closely, and SSRIs should only be used in children and young adults when the benefit clearly outweighs the risk.

You should never stop Celexa or Zoloft abruptly. You may experience withdrawal symptoms and adverse effects such as nausea, vomiting, dizziness, and headache. Your healthcare provider should be consulted before stopping these medications, and they should provide you with a safe manner to taper off of the drug.

Celexa and Zoloft have been known to cause QT prolongation, a potentially very serious side effect and can lead to death. This is an abnormality in the electrocardiogram characterized by Torsade de Pointes (TdP) and ventricular tachycardia. The risk of heart problems goes up with dose. It is important you adhere to the dosage limits set by your prescriber.

Serotonin syndrome has been reported with all SSRIs. This is a condition related to abnormally high levels of serotonin, and can result in the patient feeling agitated, dizzy, and having an increased heart rate. This can be brought on by the use of two serotonergic drugs together. It is important to refer to the manufacturer’s information on drug interactions when prescribing these drugs.

Frequently asked questions about Celexa vs. Zoloft

What is Celexa?

Celexa is a prescription antidepressant medication. It belongs to a class of medications known as selective serotonin reuptake inhibitors. It is prescribed to treat major depressive disorder, and it works by increasing available serotonin in the neuron synapse. Celexa is available in 10 mg, 20 mg, and 40 mg strengths.

What is Zoloft?

Zoloft is a prescription antidepressant medication used in the treatment of major depressive disorder as well as other anxiety and psychiatric disorders. Zoloft is in a class of drugs known as selective serotonin reuptake inhibitors (SSRIs). Zoloft is available as oral tablets in 25 mg, 50 mg, and 100 mg strengths, as well as an oral liquid concentrate.

Are Celexa and Zoloft the same?

Celexa and Zoloft are both antidepressants in the same class, but they are not the same drug. They have different active ingredients, and while both are approved in the treatment of depression, each carries some unique indications for use in other mental health conditions as well.

Is Celexa or Zoloft better?

Celexa and Zoloft have both been shown to be valuable, efficacious, and tolerable treatments for depression. However, Celexa shows an earlier onset of symptom relief which may be a significant factor in drug choice.

Can I use Celexa or Zoloft while pregnant?

Celexa and Zoloft are pregnancy category C, meaning there have not been adequate human studies to determine efficacy. The use of SSRIs must be weighed against the potential harm to the fetus while also considering the well-being of the mother.

Can I use Celexa or Zoloft with alcohol?

Patients on SSRIs are cautioned to avoid alcohol as it can increase the toxic effects of SSRIs and cause significant psychomotor impairment.