Effexor Side Effects, Withdrawal Risks & Lawsuit Information

Effexor (venlafaxine) is a prescription antidepressant used to treat anxiety and depression. Originally manufactured by Wyeth Pharmaceuticals Inc., it was discontinued in 2006. Pfizer, which acquired Wyeth, now produces the extended-release form of the drug, known as Effexor XR.

The medication is part of a class of drugs called serotonin norepinephrine reuptake inhibitors (SNRIs). SNRIs block the reabsorption of norepinephrine and serotonin in the brain, increasing the amount of these chemicals to improve energy and mood.

Despite its widespread use, the discontinued version of Effexor carried serious risks that led to regulations and lawsuits.

Effexor and Effexor XR come with risks like dependency, suicide, withdrawal and more.

Effexor has also been linked to birth defects, infant withdrawal and postpartum hemorrhage. Some of these risks have been at the center of lawsuits against Pfizer and Wyeth.

Most side effects from Effexor and Effexor XR are generally mild. They can include nausea, dizziness and dry mouth. Some of these issues may go away over time.

Nearly one-third of patients taking Effexor XR in clinical trials developed nausea, the most common side effect of the medication. Other frequently reported side effects included dizziness (20%), sleepiness (17%) and dry mouth (12%).

Sexual problems are another common problem associated with Effexor. In clinical trials, nearly 16% of participants who took Effexor reported “abnormal ejaculation.” A separate study in the journal Psychiatry Investigation found nearly 47% of individuals on venlafaxine experienced sexual dysfunction.

Although rare, Effexor and Effexor XR are associated with more severe risks. These can include issues like hypertension, serotonin syndrome and seizures.

In 2004, the FDA required that antidepressants include a black box warning about the increased risk of suicide in children and young adults. In 2007, that warning expanded to say that depression itself is linked to a higher risk of suicide.

Higher Suicide Risk and Dangerous Serotonin Levels

Like most antidepressants, Effexor has been associated with worsening depression and the emergence of suicidal thoughts or behaviors. A 2007 study found that adults using venlafaxine had a higher risk of suicide and attempted suicide than patients using other antidepressants. However, study authors noted that patients using venlafaxine started with a “higher burden of suicide risk factors.”

As with any antidepressant, the risk of suicide is greater during the “early phases of treatment,” according to the drug’s label. Young people under the age of 24 are most at risk.

Venlafaxine has also been linked to a rare but potentially life-threatening elevation in the body’s serotonin levels known as serotonin syndrome. This is because the drug increases the amount of serotonin in your system when it blocks reuptake. While rare, serotonin syndrome can be fatal if it’s not treated.

A person’s risk of serotonin syndrome is higher if they are taking other medications, like triptans, tricyclic antidepressants, fentanyl and St. John’s wort, that also increase serotonin levels. Nevertheless, serotonin syndrome has occurred in individuals taking venlafaxine alone.

A 2003 case report in the Annals of Pharmacotherapy described a 29-year-old woman who developed tremors, shivering, vomiting, diarrhea, an elevated heart rate and other symptoms of serotonin syndrome after receiving “low-dose” venlafaxine therapy of 37.5 mg per day. Doctors treated her with an anti-nausea medication and a sedative in the emergency department. Her symptoms resolved within two hours.

Increases in Blood Pressure

According to Effexor’s label, results of controlled trials found dose-related increases in systolic and diastolic blood pressure among patients. While elevations in blood pressure associated with Effexor are typically mild, some cases have been severe and required immediate treatment.

A 2014 report described a 23-year-old man who developed nosebleeds and headaches after 10 months of taking 150 mg of venlafaxine daily for depression. He ended up hospitalized in a hypertensive crisis, with a blood pressure reading of 210 over 170. His blood pressure returned to normal when he was taken off the drug.

The authors of the report noted that hypertension is most common in doses exceeding 300 mg per day and is “the most feared complication” associated with the drug’s use.

Increased Chance of Miscarriage and Birth Defects

The use of antidepressants has been linked to an increased risk of miscarriage. According to data published in the Canadian Medical Association Journal, roughly 5.5% of the women in the study who had taken antidepressants during their pregnancy miscarried.

Overall, the study found a 68% increased risk of miscarriage in women who used antidepressants during pregnancy compared to those women who never used the drugs. The study also showed that venlafaxine use, whether alone or with antidepressants from different classes, increased the risk of spontaneous abortion.

Effexor XR’s label warns that the drug should be used by expectant mothers “only if clearly needed.” Babies exposed to Effexor and other antidepressants during the third trimester of pregnancy have been born with significant problems, including:

According to Effexor’s label, these complications may represent withdrawal symptoms, serotonin syndrome or other toxic side effects of the drug.

A 2012 study using data from the National Birth Defects Prevention Study found “statistically significant associations” between venlafaxine use during the first trimester of pregnancy and several serious birth defects. These included:

The study hypothesizes that birth defects caused by venlafaxine could result from the drug interfering with “embryologic signaling pathways” that rely on serotonin and norepinephrine. Another possibility is that the women in the study who used Effexor had other risk factors.

Since Effexor and other antidepressants have been linked to miscarriage and complications in newborns, you should notify your doctor if you are pregnant or may become pregnant while taking the drug.

Appetite and Weight Loss in Children

In premarketing evaluation of the drug, decreased appetite was observed more frequently in pediatric patients treated with Effexor XR compared to those treated with placebo.

During clinical trials, 18% of pediatric patients experienced a weight loss of 3.5% or more while taking the drug. Over the course of the six-month study, both children and adolescents had height increases that were also less than expected when compared with their peers.

It’s important to note that Effexor XR’s label clearly states that “Effexor XR is not approved for use in pediatric patients.”

Interstitial Lung Disease and Eosinophilic Pneumonia

Effexor XR’s label says that it has been associated with interstitial lung disease and eosinophilic pneumonia in rare instances. Interstitial lung disease is the name for a group of diseases that can inflame or scar your lungs, resulting in a lack of oxygen. Scarring is permanent.

Eosinophilic pneumonia is a disease in which eosinophils, a type of white blood cell, accumulate in your lungs. These cells invade tiny air sacs (alveoli) in your lungs, despite the absence of infection, and make breathing difficult.

If you develop shortness of breath, a cough or chest discomfort while taking venlafaxine, the drug’s label recommends you should contact your physician and consider ceasing use of the medication.

Stopping antidepressants, including Effexor, can lead to withdrawal. This is sometimes called discontinuation syndrome. Effexor’s half-life is only four hours, so withdrawal symptoms can begin within just a few hours of lowering your dose or stopping the medication.

Although these symptoms usually don’t last long, more severe cases may continue for weeks or months.

A meta-analysis published in The Lancet Psychiatry showed that about 15% of those who discontinue their antidepressant will develop withdrawal syndrome. Certain antidepressants, including venlafaxine, are associated with a higher frequency and severity of symptoms.

To avoid discontinuation syndrome, Effexor should be discontinued gradually. Patients should be monitored for symptoms while weaning off the medication. According to the drug’s label, patients in clinical trials were successfully tapered by reducing their dosage by 75 mg every week.

If severe symptoms develop, the patient’s doctor may temporarily increase the dose and then taper the patient more slowly.

Since receiving FDA approval, both Effexor and Effexor XR have been subject to multiple actions and safety concerns. Some actions required label change updates to include warnings of increased discontinuation syndrome, serotonin syndrome and suicide.

Multiple lawsuits were filed against Wyeth and Pfizer, claiming that Wyeth failed to warn pregnant women about the risk of birth defects when taking Effexor. To streamline the legal process, these cases were grouped into multidistrict litigation (MDL) in the Eastern District of Pennsylvania in 2013. All cases were closed or dismissed in 2015.

There have also been lawsuits filed against Wyeth by the families of Effexor users who committed suicide. These plaintiffs alleged that the manufacturer failed to warn about the increased risk of suicide when taking the drug. The courts ruled in favor of Wyeth in these cases.

To date, there have been no settlements related to Effexor and birth defects or suicide risks.

Similarly, selective serotonin reuptake inhibitor (SSRI) antidepressants faced litigation regarding birth defects and the risk of suicide. These lawsuits led to millions in settlements.

If you are struggling with side effects or withdrawal symptoms, there is help available. Before you discontinue Effexor XR, it is important to have a discussion with your doctor. They can ensure you gradually decrease your dosage until you are safely off the medication.

Your provider may also recommend switching to an alternative medication.

Talk to your doctor to determine which antidepressant would be the best choice for you.

If you experience severe side effects while taking Effexor XR, call your doctor right away. Since there’s a potential for withdrawal symptoms if you suddenly stop taking the medication, you’ll need your doctor’s help to wean yourself off of it safely.

Drug manufacturers are required to provide warnings about possible risks and side effects. If product labeling or packaging is insufficient or misleading, you may be entitled to compensation.

Effexor lawsuits were filed against the drugmaker for failing to warn patients about the medication’s possible safety risks. Talk to an attorney to learn about current lawsuits and your legal options.