Possible Side Effects of EFFEXOR XR

EFFEXOR XR may cause side effects in some people. In clinical studies, few people had to stop taking EFFEXOR XR because of side effects.

In clinical studies, the most common side effects included:

  • Nausea
  • Dizziness
  • Sleepiness
  • Abnormal ejaculation
  • Sweating
  • Dry mouth
  • Gas
  • Abnormal vision
  • Nervousness
  • Insomnia
  • Anorexia
  • Constipation
  • Confusion/agitation
  • Tremor
  • Yawning
  • Palpitation

Tell your doctor right away if you have

  • increases in heart rate.
  • extreme confusion or seizures, which may indicate very low levels of sodium in the blood.
  • abnormal bleeding or bruising.
  • sudden, unexpected eye pain, eye redness, or changes in vision, which may indicate increased eye pressure.
  • symptoms of mania or hypomania, such as persistently elevated or irritable mood, a decreased need for sleep, racing thoughts, hyperactivity, and rapid, excessive speech.

EFFEXOR XR may cause an increase in your cholesterol.  Your doctor may want to do blood tests to check your serum cholesterol periodically.


What happens when I stop using EFFEXOR XR?

Symptoms are known to occur when people stop using EFFEXOR XR, especially when they suddenly stop therapy.

When people suddenly stop using EFFEXOR XR, they can get symptoms from stopping the medicine too fast.  Some of these symptoms include

  • Agitation
  • Anxiety
  • Confusion
  • Diarrhea
  • Dizziness or vertigo
  • Dry mouth
  • Fasciculation (muscle twitching)
  • Headaches
  • Hypomania
  • Impaired coordination
  • Insomnia (trouble sleeping)
  • Loss of appetite
  • Nausea
  • Nervousness
  • Nightmares
  • Sensory disturbances (including electric shock sensations)
  • Somnolence (sleepiness)
  • Sweating
  • Tinnitus
  • Tiredness
  • Tremor
  • Unpleasant mood
  • Vomiting



Do not stop taking EFFEXOR XR without talking with your doctor first.  Your doctor may want to slowly decrease your dose of EFFEXOR XR to help avoid these kinds of symptoms.

Provided by ArmMed Media
Revision date: July 9, 2011
Last revised: by Sebastian Scheller, MD, ScD