Disclaimer: None of the information in this article constitutes medical advice, and is just the opinion of the writer(s) and published for informational purposes only. We recommend that patients follow their doctor’s guidance in regard to prescription medication.
Desvenlafaxine is a prescription drug which is approved by the Food and Drug Administration (FDA) in the U.S. to treat Major Depressive Disorder (MDD). The full name of the active chemical compound is desvenlafaxine succinate, or desvenlafaxine succinate ER, but it’s typically shortened to just the first word for convenience.
Desvenlafaxine is the generic term for the drug, and its branded version is called Pristiq. We will use these terms interchangeably throughout this article because they refer to the same active chemical compound.
In this article we’ll review published medical studies on desvenlafaxine to determine if it’s effective for treating depression. We’ll highlight side effects of the medication, compare its efficacy to other generic antidepressant drugs such as venlafaxine, and share a natural, over-the-counter (OTC) treatment that patients with mild depression may want to consider.
Does Desvenlafaxine Work?
There have been a number of clinical trials evaluating the effectiveness of desvenlafaxine for reducing symptoms of depression.
One such trial published in 2012 found desvenlafaxine to be effective for patients with MDD. All patients in this trial were previously diagnosed with MDD, which is somewhat standard for antidepressant drug trials, as MDD is typically the most severe and challenging category of depression to treat.
The study authors measured patient scores on the Hamilton Depression Rating Scale (HAM-D), which is a clinical tool that measures changes in a wide variety of symptoms associated with depression, such as sleeplessness and low libido.
The trial participants assigned to desvenlafaxine reported significantly reduced depression based on the HAM-D scoring. The average HAM-D score was greater than 20 at the start of the trial and less than 10 at the end of the trial, representing a decrease in depression symptoms of over 50%.
A medical review evaluated the efficacy of desvenlafaxine for patients with major depression. This review analyzed data from three individual clinical trials on the topic.
The researchers concluded that desvenlafaxine improved the condition of depressed patients on average. Remission rates were around 10% higher in the trial participants taking desvenlafaxine compared to the trial participants taking placebo pills. Remission is defined as an extended period free of any major depressive symptoms, so this is a significant result.
A recent clinical trial examined whether desvenlafaxine could improve productivity at work for patients who were depressed and employed. The medication did not improve cognitive function or work-related outcomes.
We will conclude from the available research that desvenlafaxine effectively treats depression, but is unlikely to improve productivity at work for patients who are depressed and working a salaried job.
How Does Desvenlafaxine Work?
Desvenlafaxine is a member of a class of drugs called serotonin and norepinephrine reuptake inhibitors (SNRI). As we outlined in our Pristiq reviews article, the drug is 10 times more selective for serotonin than norepinephrine. This suggests that it has greater effects on serotonin levels in the brain than on norepinephrine.
SNRI drugs delay the body’s processing and clearance of serotonin and norepinephrine, which are neurotransmitters that have significant effects on mood. By delaying biological processing of these neurotransmitters, desvenlafaxine causes an artificial increase in their circulating levels, which can improve mood and reduce depression.
It hasn’t been conclusively proven that patients with depression have lower levels of these neurotransmitters than non-depressed patients, but this is the suggested mechanism of action. Researchers don’t have to necessarily understand how a drug works to be able to conclusively state that it’s effective to a statistically significant degree based on clinical trials.
Desvenlafaxine Side Effects
Desvenlafaxine has a “black box” warning on its FDA label, which references a risk of severe side effects. The black box warning states that desvenlafaxine may increase risk of suicidal thoughts or actions in children, adolescents and young adults.
A clinical trial published in the Current Medical Research and Opinion journal provides some useful side effect data. Around 5% more patients taking desvenlafaxine withdrew from the study because of adverse effects than those taking placebo pills. This suggests that desvenlafaxine has a greater risk of side effects than placebo.
The most common side effect documented in the above-linked trial was dizziness, which occurred 8% more frequently on desvenlafaxine than on placebo, dry mouth which occurred 9% more frequently in the desvenlafaxine group, and constipation which occurred 7% more frequently in the desvenlafaxine group.
Clearly the more common side effects of desvenlafaxine are relatively mild, but the rare risk of suicide-related side effects is concerning.
It may be beneficial for parents who are considering desvenlafaxine for their child to speak with their child’s doctor about alternative antidepressant medications without the potential for increased suicidality. It may be useful for young adults (the age range for “young adult” is not defined on the FDA label) to discuss the same concerns with their doctor.
Desvenlafaxine Vs. Venlafaxine
Venlafaxine is another commonly-prescribed antidepressant, which is sold under the brand name Effexor. Patients are often curious about which medication is more effective.
A comparative medical review published in 2012 examined the efficacy and safety of these two drugs. The researchers concluded that they were equal in terms of efficacy, but that desvenlafaxine caused fewer side effects.
Another medical review examined results when patients who were unresponsive to venlafaxine switched to desvenlafaxine. Over 50% of them were categorized as “responders” to desvenlafaxine, which suggests that the drug may be effective for patients who attained no benefit from venlafaxine.
Based on the available research, there doesn’t seem to be much clinical difference between desvenlafaxine and venlafaxine, but patients with a history of nausea may benefit from speaking with their doctor about desvenlafaxine, which may be less likely to cause nausea as a side effect.
OTC Antidepressant Option
While desvenlafaxine is prescribed for treating major depression, there exist research-backed OTC options available at drug stores, grocery stores or online that may be effective for mild-to-moderate depression with a more favorable side effect profile.
St. John’s Wort is an herbal supplement which was shown in an extensive medical review to be as effective as SSRIs for treating mild and moderate depression. The researchers conducting this review analyzed 27 individual trials on St. John’s Wort for depression.
Since herbal supplements can vary so much in terms of quality as they aren’t as strictly regulated as prescription drugs, we think it’s worth noting that most of the St. John’s Wort extract used in the medical trials was standardized to 2-5% hyperforin and 0.3% hypericin. These are the active chemical compounds in the supplement, and it seems logical to take a product with standardization ratios which mirrors that used in medical research.
We are not suggesting that St. John’s Wort is as effective an antidepressant as desvenlafaxine; just that it may be a safe and natural option for patients with milder forms of depression. We would strongly advise depressed patients to speak with their doctor prior to using St. John’s Wort, especially if they plan to use the supplement concurrently with their medication.
Taking supplements and medications which can affect serotonin metabolism can cause a rare condition called Serotonin Syndrome which is life-threatening. This is why it’s so important for patients taking any drug, OTC or prescription, for depression to speak with their doctor first.
Should I Take the Branded Version of Desvenlafaxine?
As referenced earlier in this article, the brand-name version of desvenlafaxine is Pristiq. Patients are often curious about which medication to take, given that the two terms contain the same active drug ingredient.
Because branded and generic drugs are functionally equivalent, we typically recommend that patients speak with their doctor about the generic version (in this case desvenlafaxine), because it should be equally as effective as Pristiq but may cost significantly less.
A thorough meta-study examined the relative efficacy of brand-name versus generic drugs, and found them to be equally effective on average. There were a few exceptions, but desvenlafaxine was not one of them. Thus, it seems logically sensible to consider desvenlafaxine over Pristiq, especially for patients on a lower income.
Desvenlafaxine is prescribed at multiple different doses according to StatPearls which is one of the largest free medical databases in the U.S. StatPearls reports that the starting dose of desvenlafaxine is typically 50 milligrams (mg), but that the maximum therapeutic dose is 400 mg.
We located an interesting study on dosage that’s worth highlighting. A clinical trial compared the efficacy of desvenlafaxine at 50 mg and 100 mg per day for treating MDD.
Contrary to what one might expect, the drug was actually more effective at the lower dose. Trial participants taking 50 mg daily reported lower HAM-D scores than those taking 100 mg daily.
Doctors often start patients on the lowest therapeutic dose in any case, because lower doses tend to confer a lower risk of side effects. But in light of this clinical trial, it may be worthwhile for patients to speak with their doctor about starting at a 50 mg dose, and only increasing dosage if they fail to experience benefit at that dose.
Desvenlafaxine User Reviews
Desvenlafaxine has been reviewed over 800 times on Drugs.com at the time of writing this article. This website allows users to publish reviews of prescription drugs they’re taking. We cannot verify the accuracy or legitimacy of any reviews on this website, but patients sometimes find it useful to read reviews written by people taking medication.
The average rating of desvenlafaxine for depression is 6.9/10.
The top positive review is written by a user named “Aljo” who claims the medication has provided antidepressant benefits without the sexual side effects of other medications:
“I've recently come off lexapro due to some side effects, loss of sex drive and ejaculations without orgasms. How weird is that? Anyway I'm now on [desvenlafaxine] and the fog has lifted. You forget how good life can be when you're in the spirals of depression. But be active in your care and keep trying different meds because one day you'll succeed. I think [desvenlafaxine] is my 6th attempt at finding my happy place.”
The top negative review is published by a user named “Mylifeisruined” who gave the drug a 1/10 star rating and claims that the side effects reduced their quality of life:
“I suffered almost every side effect, yawning, insomnia, increased anxiety, tinnitus, sweating, incapable of having an orgasm, vivid nightmares. I took [desvenlafaxine] 50mg for 4 weeks and I only had 1 day that I was not depressed. I quit taking it after 4 weeks of sleepless nights and a very loud high pitched ringing in my head. 2 weeks of feeling dizzy and extreme headaches, then 2 months of bad headaches and extreme anxiety.”
Desvenlafaxine Withdrawal Symptoms
Desvenlafaxine does appear to have a risk of withdrawal symptoms, which is somewhat common for drugs which modulate neurotransmitter function.
A meta-study from 2009 investigated withdrawal symptoms associated with desvenlafaxine discontinuation. The most common withdrawal symptoms were: dizziness, nausea, headache and irritability.
Patients taking higher daily doses of desvenlafaxine experienced worse withdrawal symptoms on average. After the third week, patients withdrawing from a 400 mg/day dose were still experiencing withdrawal symptoms twice as severe than patients withdrawing from a 100 mg/day dose.
We would strongly recommend that patients speak with their doctor prior to quitting desvenlafaxine use, because a trained medical professional can help reduce the risk of withdrawal symptoms by creating a tapering schedule. By slowly reducing daily dose according to research standards rather than stopping abruptly, the risk of withdrawal symptoms may be lessened.
Desvenlafaxine for Anxiety
Desvenlafaxine isn’t typically prescribed to treat anxiety, but patients are often curious about whether it may be effective given that many patients suffer from both depression and anxiety.
A medical review published in the CNS Spectrums journal assessed data from nine clinical trials on desvenlafaxine to study its anti-anxiety effects.
Those taking desvenlafaxine reported significantly reduced anxiety by the end of the trials than at baseline. Anxiety severity was an average of 14% lower in those taking desvenlafaxine than those taking placebo.
Another clinical trial evidenced similar results. Depressed patients taking desvenlafaxine were less anxious by the end of the trial
Desvenlafaxine is only FDA-approved for treating depression, so we would not recommend its use for anxiety alone, as this would be an “off-label” use which may be unsafe.
This research does suggest that desvenlafaxine may be an effective treatment option for patients with both depression and anxiety. For those prescribed desvenlafaxine for MDD, the potential anti-anxiety effects may be considered a secondary benefit.