Effexor is an SNRI antidepressant medication used to treat depression and anxiety disorders. As an off-label medication, Effexor has been used to treat pain caused by severe migraines, diabetic neuropathy, and hot flashes. It is similar to SSRIs, but some of Effexor’s side effects may be different. Severe side effects caused by Effexor have been the basis of lawsuits filed against the manufacturer.

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What Is Effexor?

Effexor is the name brand for the generic medication venlafaxine hydrochloride and is a serotonin-norepinephrine reuptake inhibitor (SNRI) antidepressant drug approved for the treatment of major depression. A controlled release form, Effexor XR is also approved to treat generalized anxiety, panic disorder, and social phobia.

How Does Effexor Work?

Effexor is an SNRI and is different than an SSRI. SNRIs work by regulating serotonin and norepinephrine reabsorption. SNRIs work to treat depression and other mental disorders by increasing the activity of neurotransmitters, or chemical messengers, serotonin and norepinephrine, in certain areas of the brain. Serotonin acts to regulate sleep and mood and may help provide the satiety or “satisfaction” sensation. Norepinephrine is made from dopamine and plays a key role in alertness, arousal, and attention. Effexor increases the levels of both serotonin and norepinephrine in the brain.

Other members of the SNRI class of medications include Cymbalta (duloxetine), Pristiq (desvenlafaxine), and Savella (milnacipran).

What Company Manufactures Effexor?

Effexor is the brand name for venlafaxine hydrochloride and was originally manufactured by Wyeth. Pfizer acquired Wyeth in 2009 and continues to manufacture Effexor. Effexor was the first SNRI antidepressant and became available in 1993. By 2007, Effexor became the sixth most popularly-prescribed drug in its class with more than 17 million prescriptions in the United States. Effexor as a “fast-release” medication is no longer manufactured by Pfizer but may still be available generically and requires multiple doses to be taken each day.

In 2007, Effexor’s then-manufacturer, Wyeth was given a warning by the U.S. Food and Drug Administration (FDA) regarding misleading advertising which had minimized the risks of Effexor and overstated its effectiveness.

Is Effexor FDA-Approved?

The U.S. Food and Drug Administration (FDA) approved Effexor in 1993 to treat depression in adults. In 1997, a controlled release form, Effexor XR, was approved to treat other conditions in adults such as anxiety, panic disorders, and social phobia. Effexor is not approved for use in children.

What Is Effexor Prescribed To Treat?

Effexor is prescribed by doctors to treat conditions it is approved to treat as well as conditions for which it is not approved. Effexor is only approved by the FDA to treat major depression.

Symptoms of major depression include:

  • Loss of interest in normal activities
  • Feelings of guilt or worthlessness
  • Excessive crying
  • Lack of energy
  • Loss of concentration
  • Changes in appetite
  • Changes in sleep patterns
  • Suicidal thoughts and tendencies

Effexor XR is approved by the FDA for major depression as well as anxiety, panic disorders, and social phobia.

What Is Anxiety?

Anxiety is a natural response to stress. It may cause feelings of nervousness or anxiousness. Anxiety can be helpful in some situations, and it may alert to danger or help a person pay attention. Anxiety in general differs from anxiety disorders, which are characterized by excessive worry, fear, or anxiety which are not proportionate to the situation and affect a person’s ability to function normally.

What Are Panic Disorders?

Panic disorders are one variety of anxiety disorders. People with panic disorder experience unanticipated and recurrent episodes of heightened fear that are coupled with physical symptoms such as chest pain, shortness of breath, dizziness, heart palpitations, or abdominal discomfort or distress. Episodes caused by panic disorder are not induced by an obvious stressor.  

What Is Social Phobia?

Social phobia, or social anxiety disorder, is another variety of anxiety disorder. A person who has social anxiety disorder experiences extreme anxiety, self-consciousness, and embarrassment because they fear others are scrutinizing them or negatively judging them. People with a social anxiety disorder may avoid various situations where they may be the center of attention or fear embarrassment if they do something or speak out.

Is Effexor Prescribed To Treat Other Conditions?

Effexor is sometimes prescribed “off-label” to treat other conditions than those for which it is approved. When a medication is prescribed off-label, that means that it does not have FDA approval to treat that condition. Federal law allows for medications to be prescribed for non-approved conditions, but pharmaceutical companies are prohibited from marketing medications to treat those non-approved conditions.

Conditions for which Effexor has been prescribed off-label include:

  • Attention deficit/hyperactivity disorder in both adults and children
  • Obsessive-compulsive disorder (OCD)
  • Posttraumatic stress disorder (PTSD)
  • Premenstrual dysphoric disorder (PMDD)

Some physicians have prescribed Effexor to treat pain caused by severe migraines, diabetic neuropathy, and hot flashes. Before prescribing Effexor for any of these off-label uses, doctors should justify their reasoning and discuss it with their patients.

Does Effexor Cause Side Effects?

Effexor, like most medications, causes side effects in some patients. Most of these side effects are mild and will go away on their own with time. However, some patients may experience severe side effects and should seek medical attention right away. These severe side effects are dangerous and may become life-threatening in some cases.

Mild side effects caused by Effexor include:

  • Dry mouth
  • Dizziness
  • Nausea
  • Headache
  • Blurred vision
  • Increased sweating
  • Nervousness or insomnia
  • Drowsiness or fatigue
  • Constipation
  • Strange dreams
  • Appetite and weight change
  • Decreased libido, sex drive, and difficulty achieving orgasm

Can Effexor Cause Severe Side Effects?

Effexor can cause severe side effects. These side effects should be reported to a healthcare professional immediately.

Severe side effects caused by Effexor may include:

  • Trouble breathing or tightness in the chest
  • Memory
  • Hallucination
  • Seizures
  • Fever, nausea, or vomiting
  • Increased heart rate or blood pressure
  • Hostility, agitation, aggression
  • Suicidal thoughts or behavior
  • Sudden changes in moods or behavior
  • Anxiety or panic attacks

Effexor may cause side effects that are significant and may be life-threatening. These side effects have been the basis of lawsuits filed against the manufacturer. These are:

  • Birth defects
  • Serotonin syndrome
  • Withdrawal or discontinuation syndrome

Is Effexor Safe To Take When Pregnant?

Effexor use has been associated with a number of birth defects when the drug is taken during pregnancy. The FDA has given venlafaxine a pregnancy category of C which indicates that Effexor has caused harm to animals during testing but has not been fully tested in humans.

The Canadian Medical Association Journal published a study in 2010 on venlafaxine, the active ingredient in Effexor. The study indicated that the risk of miscarriage was doubled in women who took the drug during pregnancy.

Effexor may cause “non-teratogenic effects” in newborns. These effects are not birth defects, but they may include complications that require lengthened hospital stays, respiratory support, and the use of a feeding tube after delivery.

Serious effects in newborns noted with Effexor may include:

  • Respiratory distress
  • Cyanosis
  • Apnea
  • Seizures
  • Temperature instability
  • Difficulty feeding
  • Constant crying
  • Irritability
  • Vomiting
  • Hypotonia
  • Hypoglycemia
  • Jitteriness
  • Tremor
  • Hypertonia
  • Hyperreflexia

Is Effexor Linked to Birth Defects?

Pregnant or nursing mothers face serious risks. Effexor carries the potential risk of birth defects and may be linked to serious complications in some pregnancies. These include:

  • Persistent pulmonary hypertension of the newborn (PPHN)
  • Respiratory distress
  • Heart defects and malformations
  • Physical defects such as cleft lip and palate
  • Anencephaly – the absence of parts of the brain and skull
  • Craniosynostosis – causes abnormal skull and brain growth
  • Omphalocele – an abdominal defect that causes organs to protrude from the belly button

Is It Safe To Take Effexor While Breastfeeding?

After birth, nursing infants may still develop side effects related to Effexor use from their mothers.

Newborns may develop symptoms such as:

  • Irregular appetite or difficulties feeding
  • Heart defects
  • Growth or development defects
  • Jitteriness or shaking
  • Seizures
  • Consistent or abnormally frequent crying

Does Taking Effexor Cause Serotonin Syndrome?

Though it most commonly occurs in SSRI-type antidepressants, SNRI medications such as Effexor may also result in excessive serotonin buildup in the brain. It is more likely if the SNRI is taken with other medications that also affect serotonin including treatments for migraine, cough suppressants, and certain herbal remedies.

Symptoms may include:

  • Sudden spikes in blood pressure or heart rate
  • Higher than normal body temperature
  • Unexpected muscle contractions
  • Changes in mental status
  • Loss of consciousness

Symptoms of serotonin syndrome should be treated as an emergency. In some cases, serotonin syndrome may be life-threatening. All medications should be discussed with a physician to avoid drug interactions.

Does Stopping Effexor Cause Withdrawal or Discontinuation Syndrome?

Experts recommend that patients consult a physician before stopping Effexor use. Stopping too soon or abruptly can lead to withdrawal symptoms or discontinuation syndrome.

Effexor withdrawal symptoms may include:

  • Loss of coordination
  • Stomach cramps
  • Severe headaches/migraines
  • Extreme sleepiness
  • Fatigue

Have Lawsuits Been Filed Because of Effexor?

After its acquisition of Wyeth, Pfizer assumed responsibility for Effexor’s liability including lawsuits filed due to medical injury. Pfizer has faced multiple lawsuits after Effexor was used during pregnancy and may have caused birth defects. Women have said that they would not have used Effexor during pregnancy if they had been properly warned of the risk. The company may also face lawsuits for other side effects or medical injuries. People or loved ones of those who experienced harm due to Effexor should seek legal assistance.

What Types of Lawsuits Have Been Filed Regarding Effexor?

There are two main types of lawsuits that have been filed regarding potential claims patients and their loved ones may have against the manufacturer of Effexor. These two lawsuit types are:

  1. Product liability
  2. Wrongful death

Both lawsuit types can result in monetary awards to the Plaintiff. They also help to raise awareness about dangerous products.

What Are Product Liability Lawsuits Involving Effexor?

A medication manufacturer is charged with ensuring its medications are not unreasonably dangerous to patients and are safe for patients to take. Plaintiffs who have filed Effexor lawsuits allege that the manufacturer did not provide adequate warnings about the possible severe risks of taking Effexor. The plaintiffs argue that the injuries they or their loved ones sustained would not have resulted had they been properly warned about the risks associated with taking Effexor.

What Are Wrongful Death Lawsuits Involving Effexor?

A wrongful death lawsuit can be brought by certain immediate family members of a deceased person against the individual or company that caused the loved one’s death. Those family members or close loved ones who may sue vary depending on state laws. Wrongful death lawsuits have been brought against the manufacturer of Effexor in situations where a baby died because of a birth defect linked to Effexor and in situations where it is alleged that Effexor led to suicide.

What Effexor Lawsuit Settlements Have There Been?

As of 2016, all federal lawsuits involving Effexor were dismissed but left with the possibility of being refiled. Effexor patients who believe that Effexor has caused harm may be eligible to receive a settlement from Wyeth and should seek legal advice.

Notwithstanding claims relating to this product, the drug/medical device remains approved by the U.S. FDA. 


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