If you, in addition to your prescribing doctor or nurse, want to search and be more informed, you can do that by narrowing the search to a certain category of antidepressant, such as the serotonin reuptake inhibitors (SSRIs). SSRIs are the most commonly prescribed type of antidepressants. Two SSRIs you might want to learn more about and consider are Zoloft and Prozac.
How might you know which one of these two is right for you? Zoloft or Prozac? There is no “one-size-fits-all” answer to that question, because the right medication will depend on many different factors, such as:
This Minded Medication Guide will take a deeper look at Zoloft and Prozac to help you understand which antidepressant may be the better choice for you, whether this is your first time taking one of these medications, or you are considering switching from Zoloft to Prozac (or switching from Prozac to Zoloft). This information can be helpful to you when talking with your doctor, prescribing nurse, or the experts at Minded in determining the depression medication used in your treatment plan.
Read on to learn more about these two medications, including:
The information contained in this article is intended as an educational aid only. It is not intended as medical advice for individual conditions or treatment. It is not a substitute for a medical exam, nor does it replace the need for services provided by medical professionals. Talk to your doctor, nurse or pharmacist before taking any prescription medication or following any treatment or regimen.
There are several types of antidepressant medications. They are generally grouped by how and which neurotransmitters (small molecules in the brain that pass messages from nerve to nerve) they affect to relieve the symptoms of depression. As mentioned above, Zoloft and Prozac are both selective serotonin reuptake inhibitors (SSRIs).
Serotonin (a neurotransmitter) helps balance your mood and plays a role in feeling satisfaction, happiness, and optimism, as well as a sense of overall well-being. When the serotonin level in your brain is too low, you may feel depressed. SSRIs increase your level of serotonin by preventing it from being reabsorbed into your neurons (the term for the nerves in your brain). Preventing reabsorption allows more serotonin to remain available in your brain.
SSRIs (like Zoloft and Prozac) are the most commonly prescribed type of antidepressants. While they are considered safe for most people, that is not to say they are entirely risk-free. For instance, SSRIs may interact with other medications and may cause symptoms of physical withdrawal and renewed mood problems, if stopped abruptly.
While Zoloft and Prozac are both SSRI antidepressant medications, they do have differences. Taking a closer look at each of them can help you determine which medication may be a better choice for you.
Zoloft is the brand name of the generic drug sertraline. It was approved by the Food and Drug Administration (FDA) in 1999 and is used to treat depression, obsessive-compulsive disorder (OCD), panic disorder, premenstrual dysphoric disorder (PMDD), social anxiety disorder, and post-traumatic stress disorder (PTSD). One reason to know this is that depression is frequently accompanied by anxiety (which Zoloft can help).
Zoloft sometimes also is prescribed for “off-label” uses. “Off-label” use means taking a medication for a condition that it has not been approved by the FDA to treat, a common and acceptable medical practice. Zoloft may be used “off-label” to help treat binge-eating disorder, bulimia nervosa, and generalized anxiety disorder (GAD).
Zoloft (sertraline) is available in tablet and liquid forms:
Your doctor or prescribing nurse may initially start you on a lower dose, such as 50 mg, and then increase the dosage gradually over the course of several weeks, if needed. The highest dose of this medication usually is no more than 200 mg daily, though some people need higher doses to achieve symptom relief.
Zoloft is taken once a day. It can be taken in the morning or at night, with or without food.
If you miss a dose of Zoloft, you will want to either: Take the missed dose as soon as you remember, or if it is closer to the time when you would take your next dose, just take the next dose.
When you first start taking Zoloft, you may notice that your sleep, energy, and/or appetite begins to improve within the first two weeks. However, it can take up to 6 to 8 weeks for improvement of a depressed mood or decreased interest in activities to become noticeable.
Common side effects of Zoloft include:
These side effects typically decrease during the first few weeks of taking Zoloft.
Zoloft may also lead to a decreased sex drive or trouble performing sexually; these sexual side effects, however, may not decrease over time.
Talk to your doctor or the experts at Minded if you experience any of these or other side effects.
Rare or serious side effects of Zoloft include:
SSRI antidepressant medications, like Zoloft, may also put you at an increased risk for bleeding, especially when they are taken with medications such as aspirin, nonsteroidal anti-inflammatories (NSAIDs—like ibuprofen or naproxen), and warfarin (an anticoagulant medication), or other anticoagulants. Zoloft with any single or combination of these medications could cause your gums, nose, stomach, or intestines to bleed more easily. Bleeding in these areas can be life-threatening.
Seek medical attention right away if you experience any of these (or other) serious side effects.
Zoloft comes with an FDA “Black Box” warning, which means that the FDA has identified certain serious safety risks from taking it. Though these are serious safety warnings, the actual risk may be very low, even rare.
The Black Box warning for Zoloft states that antidepressants may increase the risk of suicidal thoughts or behaviors in children and young adults under 25 years old.
If you are planning on becoming pregnant, it is important to discuss your depression treatment plan with your doctor, as taking SSRIs (like Zoloft) during pregnancy or while breastfeeding may impact your baby.
Drinking alcohol is not recommended while taking Zoloft. Alcohol can decrease the benefits of antidepressant medications and increase their side effects (such as sedation).
If you need to stop taking Zoloft, work with your doctor to discuss how to do so carefully in order to avoid withdrawal symptoms (such as agitation or anxiety, dizziness, headache, and nausea).
Let your doctor or a Minded professional know about any other medications you are taking to determine if Zoloft might have any negative interactions with them.
Prozac is the brand name of the generic drug fluoxetine. Like Zoloft, it was approved by the FDA in 1999. In addition to major depressive disorder (MDD), Prozac is used to treat obsessive-compulsive disorder (OCD), panic disorder, bulimia nervosa, and premenstrual dysphoric disorder (PMDD).
Prozac is sometimes used “off-label” for body dysmorphic disorder, binge eating disorder, generalized anxiety disorder (GAD), social anxiety disorder, dysthymia, and post-traumatic stress disorder (PTSD).
Prozac (fluoxetine) is available in multiple forms and doses:
Prozac Weekly Capsules
When you first start taking Prozac, your doctor may prescribe a lower dose, such as 20 mg, and then increase the dosage slowly over several weeks or longer, if necessary. Its highest dose is usually no more than 80 mg daily, though some patients require and can benefit from greater daily doses. Once you are on the right dose for your needs, your doctor may switch you to a weekly dose, which means you would only have to take this medication one day each week. Prozac stays in the bloodstream long enough to permit weekly dosing.
Prozac is taken once a day, typically in the morning, with or without food.
If you miss a daily dose of Prozac, you will want to either: Take the missed dose as soon as you remember, or if it is closer to the time when you would take your next dose, just take the next dose.
If you are on the once-weekly dose of Prozac and you miss the dose, take the missed dose as soon as possible and then resume your normal medication schedule.
So how long does it take for Prozac to work? As with Zoloft, you might begin to notice that your sleep, energy, and/or appetite start to improve within the first two weeks of taking Prozac. However, it may take up to 6 to 8 weeks, or longer for improvement of low mood and lack of interest (common depression symptoms) to become noticeable.
Common side effects of Prozac include:
These side effects generally improve during the first few weeks after you begin taking Prozac.
Prozac also can decrease your sex drive and impair sexual performance. However, as with Zoloft, this side effect may not go away while you are on the medication.
Talk to your doctor if you experience any of these or other side effects.
Rare or serious side effects of Prozac include:
And because it is an SSRI, Prozac also may increase your risk for bleeding, especially if you are also taking medications such as aspirin, nonsteroidal anti-inflammatories (NSAIDs—like ibuprofen or naproxen), and warfarin or other anticoagulant drugs. Prozac in combination with one or more of these medications may cause your gums, nose, stomach, or intestines to bleed more easily, which can be life-threatening.
Seek medical attention right away if you experience any of these (or other) serious side effects.
Like Zoloft, Prozac has an FDA Black Box warning about antidepressants possibly increasing the risk of suicidal thoughts or behaviors in people under 25 years of age.
Because Prozac is an SSRI, it can affect a baby during pregnancy and while breastfeeding. Be sure to discuss your depression treatment plan with your doctor if you are or plan to become pregnant, or are breastfeeding.
You should not drink alcohol while taking Prozac. Alcohol can decrease the benefits of antidepressant medications and increase their side effects (such as sedation).
Prozac can also cause withdrawal symptoms if you stop taking it suddenly, so it is important to talk with your doctor to come up with a plan to carefully go off of it, if needed.
Tell your doctor or a Minded professional about any other medications you may be taking to determine if Prozac might have any negative interactions with them.
Zoloft and Prozac both take several weeks before you may start to notice an improvement in your depression symptoms. Because neither one has an advantage over the other in this area, it is not generally a factor in decision-making when choosing between the two medications.
You may notice an improvement in your sleep, energy, and appetite within the first two weeks of starting Zoloft or Prozac. It may take up to 6 to 8 weeks for other symptoms—such as depressed mood or decreased interest in activities—to get better as well.
The good news is that both Zoloft and Prozac are comparable in terms of being able to effectively treat major depressive disorder (MDD), according to a study published in International Clinical Psychopharmacology. The study found that both people on Zoloft and people on Prozac showed measurable improvement in their symptoms—and this improvement was maintained for the duration of the study.
However, while both medications were found to be similarly effective, the study also found that around 10% of people stopped taking Zoloft because it was not working for them, compared to around 20% of people who stopped taking Prozac for the same reason. In other words, when they work, both work comparably well. But more people may find that Zoloft works for them compared to Prozac.
The study also found that the rate of adverse events (side effects) was similar for both medications, meaning around the same percentage of people taking each medication experienced side effects. The people taking sertraline (Zoloft), however, rated the side effects as less severe compared to the people taking fluoxetine (Prozac).
While Zoloft and Prozac have many of the same potential side effects, each comes with its own list of more common side effects to watch out for and bring to your doctor’s attention.
Common side effects of Zoloft that you should notify your doctor of right away include:
Other common side effects of Zoloft that you may also want to mention to your doctor include:
Common side effects of Prozac that you should notify your doctor of right away include:
Other common side effects of Prozac that you may also want to mention to your doctor include:
You might have heard that antidepressant medications can cause weight gain. Some antidepressants do appear to have a higher rate of weight gain than others. Sometimes, however, weight gain while on antidepressants may not be directly caused by the antidepressant medication.
For instance, some people lose weight when depressed and before treatment has begun. As your appetite returns from the effective treatment of your depression, you may begin to gain that weight back, though not necessarily because of the medication itself, but rather from the reduction in the symptoms of depression.
That being said, one study published in 2016 in the Journal of Clinical Medicine found that Zoloft can lead to an overall greater weight gain than Prozac when taken long-term. The study found that people taking Prozac for two years gained an average of 4.6 pounds. But people taking Zoloft gained an average of 10.5 pounds over the same two-year period.
Zoloft and Prozac should not be taken together. Because they are both SSRIs, taking them together can cause dangerously high amounts of serotonin to collect in your body, which can lead to the potentially fatal condition noted above, serotonin syndrome.
You may consider switching from Zoloft to Prozac (or vice versa) if you have been on the medication at the right dose (as determined by you and your doctor or nurse practitioner) for several weeks with no improvement in your depression symptoms, or if you are experiencing side effects that you find too difficult to tolerate.
A not uncommon problem is when someone who was deriving benefit from taking an SSRI (like Zoloft or Prozac), begins not to have the same beneficial effect they previously had. This is a time to consider switching from one to the other, or considering a different class of antidepressants (of which there are several). Speak to your doctor, prescribing nurse, or a Minded professional about what your options may be. Depression can be effectively treated but may require changes in your medication over time.
Because both Zoloft and Prozac can cause withdrawal symptoms if stopped suddenly, switching from one to the other should be done carefully and gradually. Work with your doctor or a Minded professional to develop a plan, which may involve tapering down the dose of the medication you are currently on and then beginning the new medication.
Prozac and Zoloft are both antidepressants worth considering when building your depression treatment plan. Each comes with its own pros and cons. For instance, while both are similarly effective in treating MDD, more people may find Zoloft works for them compared to Prozac, and vice versa. While Zoloft may cause more potential and common side effects, these may be more tolerable to you than the common side effects of Prozac, and vice versa as, for example in not experiencing the more common side effect of weight gain, over time, from Zoloft than Prozac.
Seeking medical advice from your health care provider or the experts at Minded can help you understand and decide which medication may be the better fit for you.