Venlafaxine HCl extended-release, marketed by Pfizer as Effexor XR, is antidepressant approved for the treatment of depression, generalized anxiety disorder, social anxiety disorder and panic disorder. The medication works by inhibiting the re-uptake of the neurotransmitters serotonin, norepinepherine and dopamine. These chemicals are used by the brain to transmit messages related to mood, appetite, arousal and cognitive processes. Pfizer recommends that patients consult with a doctor prior to stopping treatment in order to avoid adverse reactions.
Gastrointestinal Upset
An article published in 2005 in the journal "Medscape: General Medicine" lists loss of appetite, nausea, vomiting and diarrhea as symptoms that are sometimes seen after abrupt discontinuation of venlafaxine. Another study published in 2006 in "American Family Physician" noted that withdrawal from venlafaxine and related drugs caused flu-like symptoms in some patients.
Headaches
A 2007 article published in "Advances in Psychiatric Treatment" noted that headaches are one of the most common features of the antidepressant discontinuation syndrome. Headache, and other symptoms such as sweating, are usually short-lived.
Mood Changes
A 2005 article published in "Medscape: General Medicine" warned that mood changes, including depressed mood, anxiety and agitation, are associated with abrupt Effexor XR discontinuation.
Sensory Disturbances
Sensory disturbances include electrical "popping" sensations inside the head and tingly, numb feelings in the arms and legs. Additionally, balance may be disturbed and cause feelings of dizziness or vertigo.
References
- Effexor XR General Information
- Effexor XR Prescribing Information
- "Medscape: General Medicine"; Venlafaxine and Serious Withdrawal Symptoms; Daniel M. Campagne, Ph.D.; July 2005
- "American Family Physician"; Antidepressant Discontinuation Syndrome; Christopher H. Warner, et al.; August 2006
- "Advances in Psychiatric Treatment"; Recognizing and Managing Antidepressant Discontinuation Symptoms; Peter M. Haddad and Ian M. Anderson; November 2007
