Paxil vs Zoloft: Comparing medications

Living with a mental health condition such as depression, an anxiety disorder, or OCD isn’t easy. Symptoms can affect your functioning and prevent you from living life to the fullest. Finding the right treatment to manage your symptoms and improve your mental well-being can be life-changing. Paxil (paroxetine) and Zoloft (sertraline) are two popular antidepressants that psychiatrists often prescribe to people struggling with mental health.  

While these psychiatric medications are very similar and share many similarities, there are some important differences to consider, which might influence which one is a better fit for you.  

Read on to learn about the similarities and differences between Paxil and Zoloft, drug interactions, cost, and more.  

Similarities between Paxil and Zoloft

Paxil (paroxetine) and Zoloft (sertraline) share some major similarities, including:

They’re both SSRI antidepressants

Paxil and Zoloft are both SSRIs (AKA selective serotonin reuptake inhibitors). This means they have the same mechanism of action.

SSRIs impact serotonin, a neurotransmitter that works as a chemical messenger in the brain. Low serotonin levels are thought to be linked to mental health conditions like anxiety disorders and depression.  

SSRIs work by inhibiting the reuptake of serotonin in the brain. Essentially, this means they block its reabsorption. In turn, more serotonin is available. This additional serotonin improves communication between neurons (nerve cells), helping to lessen symptoms of various conditions.  

They treat some of the same conditions

Paxil and Zoloft are both FDA-approved to treat the following conditions:

• Major depressive disorder (MDD)

• Obsessive-compulsive disorder (OCD)

• Panic disorder (PD)

• Post-traumatic stress disorder (PTSD)

• Social anxiety disorder  

They both carry the risk of serotonin syndrome

All SSRIs, including Paxil and Zoloft, can potentially cause serotonin syndrome. This is a rare but dangerous condition when your body has dangerously high serotonin levels, which there is a risk for when you  are taking a high dosage of SSRIs, especially in conjunction with other medications and supplements that affect serotonin. In severe cases, it can be fatal, but this is rare.  Symptoms range from mild (like nausea, diarrhea, and dilated pupils) to severe (like confusion, fast heart rate, high blood pressure, and seizures).  

If you notice any unusual or worsening symptoms, contact your doctor.  

They both have black box warnings

Although it sounds counterintuitive for antidepressant medications to worsen depression, it is possible. Both medications can worsen depression symptoms, result in suicidal thoughts, or cause unusual behavior. The risk of this happening is higher in people under 24 years old. If you experience any of this,suicidal thoughts, contact your doctor right away and call 911 or go to the ER immediately for an evaluation.  

Learn more about antidepressants and teens

What are their differences?

They have different FDA-approved uses

Although Paxil and Zoloft share five of the same FDA-approved indications, there are two that differ:

• Paxil is FDA-approved for generalized anxiety disorder (GAD)

• Zoloft is FDA-approved for premenstrual dysphoric disorder (PMDD)

They’re suitable for different ages

Zoloft is FDA-approved for children and adolescents ages six and up with OCD. It’s possible for doctors to prescribe Zoloft off-label to kids and teens for other mental health conditions, but this will be on a case-by-case basis.  On the other hand, the FDA explicitly states that children should not take Paxil.  

More on antidepressants and teens here.

They have different dosages

These medications don’t share the same dosing structure.  

The starting dose for Zoloft is around 25 mg or 50 mg, and the maximum dose is generally100 mg to 200 mg, depending on the condition you’re taking it for. Your psychiatrist will work with you to determine the appropriate dose.

For Paxil, the starting dose is 10 mg or 20 mg, and the maximum dose is generally 50 mg or 60 mg per day. Again, this depends on the condition for which you take the medication.  

Zoloft might be safer during pregnancy

Although there are potential risks with both SSRIs, there is some evidence that Paxil is more dangerous to take during pregnancy than Zoloft is. Taking either medication early in pregnancy may lead to cardiovascular malformations, and taking the drug later in pregnancy can cause breathing problems for the newborn. This is a rare occurence though and something you should discuss with your psychiatrist and OB/GYN. You can weigh the pros and cons. In some situations, your doctors may decide the benefits of staying on the medication outweigh the risks.  

Paxil may result in worse discontinuation symptoms

If and when you and your doctor decide it’s time to come off of your medication, you might have more severe withdrawal symptoms if you take Paxil, compared to other SSRIs like Zoloft. Even if you wean off the medication slowly, you may still experience withdrawal. This is due to Paxil having the shortest half-life amongst SSRIs.  

Withdrawal symptoms include:  

• Dizziness

• Vivid dreams

• Irritability

• Anxiety

• “Brain zaps” which feel like small electric shocks

What are their side effects?

Since they are both SSRIs, Paxil and Zoloft do share some crossover among the drugs. However, people who take Zoloft typically experience fewer side effects. They also may experience the same side effect but to a lesser degree concerning sexual side effects and weight gain with Zoloft as compared to Paxil.

Common side effects of Paxil include:

• Drowsiness

• Nausea

• Dizziness

• Diarrhea

• Constipation

• Insomnia

• Loss of appetite

• Dry mouth

• Weakness

• Sexual dysfunction (loss of libido, struggles with orgasm or ejaculation)

• Nervousness

• Increased sweating

• Yawning

• Shaking

• Infection  

Common side effects of Zoloft include:

• Nausea

• Indigestion

• Diarrhea

• Loss of appetite

• Drowsiness

• Insomnia

• Increased sweating

• Sexual dysfunction (loss of libido, struggles with orgasm or ejaculation)

• Anxiety

• Agitation

• Shaking

This is not an exhaustive list of side effects. You may experience more uncommon adverse effects when taking these drugs. Discuss any specific concerns with your doctor.  

What are their drug interactions?  

Since Paxil and Zoloft are the same type of medication, they share many of the same drug interactions, including:

• Monoamine oxidase inhibitors (MAOIs)

• Pimozide

• Triptans

• Tricyclic antidepressants (TCAs)

• Fentanyl

• Lithium

• Tramadol

• Tryptophan

• Buspirone

• St. John’s Wort

• Blood thinners (like aspirin or warfarin) which can increase the risk of bleeding

This is not an exhaustive list of drug interactions, and there are some interactions that are unique to Paxil or Prozac. Always tell your doctor about all over-the-counter and prescription medications, vitamins, and supplements that you take so they can make sure the drug is safe for you.

How much do they cost?

Paxil and Zoloft are available in both brand-name and generic versions.  

Brand name Zoloft can cost around $500 for a month, and Paxil can cost around $300 for a month. Generic versions are significantly cheaper. The price you pay will vary based on your insurance coverage and benefits. Your geographic location and the specific pharmacy you go to can also impact the price.  

Should I take Paxil or Zoloft?

Whether you choose to take Paxil or Zoloft will be a personal decision. A psychiatrist will be your best guide to help determine the best treatment plan for you. Your doctor will take your symptoms and history into account when deciding which SSRI might be more effective in your case.  

Everybody’s different and responds to medication differently. Finding the right prescription for you can take some time and trial and error. You’ll have to be patient to feel the effects of Paxil or Zoloft since it can take several weeks to notice significant improvement from SSRIs.

If you’re looking for a psychiatrist, consider Talkiatry. We’re a national psychiatry practice that treats mental health conditions, including anxiety, depression, OCD, panic disorder, PTSD, and more. We provide virtual, in-network services so you can get the care you need from home.  

To get started, complete our free online assessment to get matched with a psychiatrist.  

FAQs

What are the downsides of Paxil?

There are a few downsides of Paxil compared to Zoloft, including:

• Slightly higher risk of side effects, including weight gain.  

• Potentially more severe withdrawal symptoms if you stop taking Paxil

• May not be as safe as Zoloft during pregnancy  

Is Paxil stronger than Zoloft?

One medication isn’t necessarily stronger than the other. It depends on various factors, including the condition being treated, individual response to the medication, and your dosage. Research has shown both medications to be comparable in effectiveness. However, everyone’s different, and Paxil might work better for one person, while Zoloft might be better for another. Genetically, if a patient's family member has responded well to a medication, then they may respond well to it too. However, there are other factors to consider as discussed above when choosing an SSRI as well

What are other antidepressants?

If Zoloft and Paxil aren’t the right fit for you, there are plenty of other treatment options and antidepressant medications to choose from.  

Other SSRIs are:

• Citalopram (Celexa)

• Escitalopram (Lexapro)

• Fluoxetine (Prozac)

On top of the SSRI drug class, other types of antidepressants include:

• SNRIs (serotonin and norepinephrine reuptake inhibitors) like Effexor (venlafaxine)

• Atypical antidepressants

• TCAs (tricyclic antidepressants)

• MAOIs (monoamine oxidase inhibitors)

You and your psychiatrist will decide which specific antidepressant may be the  best option for you based on available information and your comfort level.    

The information in this article is for education and informational purposes only and should never be substituted for medical advice, diagnoses, or treatment. If you or someone you know may be in danger, call 911 or the National Suicide and Crisis Lifeline at 988 right away.