Anxiety Medications: Effexor

by Eileen Bailey Health Writer

Generic name: Venlafaxine

Effexor is an SNRI (serotonin-norepinephrine reuptake inhibitor) antidepressant, also used for the treatment of anxiety. This medication helps to balance chemicals in the brain (serotonin and norphinephrine) to decrease nervousness and agitation, to increase energy and to decrease symptoms of depression.

Effexor is available in a short-acting and an extended release medication. Generally, people must take this medication for a period of several weeks before feeling the full effects.

Children and elderly patients may be more susceptible to the side effects of Effexor. Caution should be used if this medication is given to either children or elderly patients.

Stopping Effexor can cause withdrawal symptoms. You should not suddenly stop taking this medication and should always talk with your doctor about discontinuing use of Effexor. Your doctor may want you to taper down your use of Effexor, rather than discontinuing use all at once. Tapering your use of this medication may reduce or decrease symptoms of withdrawal. Symptoms of withdrawal can include: mood changes, tingling of the skin, headache, confusion, sweating, loss of coordination, insomnia or extreme tiredness.

Before Taking Effexor

As with all medications, Effexor can cause interactions with other medications. It is important to discuss any medications, including over-the-counter medications, herbal supplements and vitamins that you may be currently taking with your doctor.

In addition, people with certain medical conditions should either not take Effexor or may require an adjustment in dosage. Talk with your doctor about any medical conditions you may have, especially:

  • Bipolar or other mental health disorders

  • History of substance abuse

  • Seizures or seizure disorders, such as epilepsy

  • Heart disease or other heart problems, including irregular heart beat

  • High blood pressure

  • Thyroid conditions

  • Liver or kidney disease

  • Lung problems

  • Glaucoma

  • Bleeding disorders

  • Stomach or bowel disorders or bleeding

  • Problems with metabolism

Side Effects of Effexor

Many people take Effexor without experiencing any type of side effects or may have mild side effects that last a few days or a few weeks and then disappear. For some people, however, side effects may persist or interfere with daily activities.

Talk with your doctor if you are experiencing any of the following side effects and they are interfering with daily life:

  • Increased anxiety

  • Blurred vision

  • Decrease in sexual desire or inability to perform sexually

  • Dizziness or drowsiness

  • Headache

  • Loss of appetite, stomach problems or constipation

  • Insomnia

This is not a complete list of possible side effects, if you are experiencing other side effects, talking with your doctor should help you determine if you should seek additional medical help.

Some side effects require you to seek immediate medical help. For the following side effects, call 911 or visit the nearest emergency room:

  • Allergic reaction, including hives, itching or trouble breathing

  • Chest pain, tightness in the chest, palpitations or irregular heartbeat

  • Sudden or severe mood changes or bizarre behavior

  • Fever, chills, swelling of the throat or mouth

  • Memory problems

  • Increased anxiety including panic attacks

  • Tinnitis (ringing in the ears)

  • Seizures, tremors or confusion

  • Shortness of breath or difficulty breathing

  • Bruising or bleeding easily

  • Vision problems

In addition, some people have experienced increased thoughts of suicide or a deepening of depression when taking this medication. If you are having thoughts of suicide or your depression/anxiety increase, contact your doctor immediately or seek emergency medical care.

Serotonin syndrome may also occur. This is possibly fatal and may happen if you take Effexor while taking MAOIs or triptan antidepressanst. Symptoms of serotonin syndrome can include agitation, confusion, hallucinations, coma, rapid heartbeat, nausea, vomiting or diarrhea. Contact your doctor immediately if you are experiencing these symptoms.

Drug Interactions

Some medications may interfere with the effectiveness of Effexor, or Effexor may interfere with the effectiveness of other medications. It is important to discuss all medications you are currently taking with your doctor. This includes supplements, over-the-counter medications and vitamins.

In particular, you want to make your doctor aware of the following medications:

  • Diet medications

  • MAOIs

  • Antidepressants

  • St. John's wort

  • Anticoagulants (including aspirin and ibuprofen)

  • Diuretics

  • Antifungal medication

  • Antipsychotic medications

Pregnancy and Nursing

Effexor may cause harm to an unborn child, especially if used during the last trimester of pregnancy. If you are pregnant, or plan to become pregnant, talk with your doctor about the possible benefits of taking Effexor and the risk to your unborn child. You and your doctor can determine if the benefits outweigh the risks involved.

Effexor can also be passed to a child through breast milk. You should not take Effexor when breast-feeding.


"Effexor", 2009, March 4, Author Unknown,

"Effexor Oral", 2007, Author Unknown, First DataBank, Inc., Health Central

"Effexor", 2009, Author Unknown, RxList

Eileen Bailey
Meet Our Writer
Eileen Bailey

Eileen Bailey is an award-winning author of six books on health and parenting topics and freelance writer specializing in health topics including ADHD, Anxiety, Sexual Health, Skin Care, Psoriasis and Skin Cancer. Her wish is to provide readers with relevant and practical information on health conditions to help them make informed decisions regarding their health care.