Effexor, also known as venlafaxine, is an oral antidepressant that functions by increasing levels of nervous system chemicals (known as serotonin and norepinephrine). Effexor is metabolized in the liver and eliminated in the urine. However, like all medications, it carries its own risk of side effects that must be weighed by the patient before beginning therapy.
Neurologic Effects
Effexor has many side effects on the nervous system. They include drowsiness, anxiety, dizziness, seizures, hot flashes and insomnia. Mania is also a side effect that is common to all antidepressants that can also occur with effexor use. The visual system can also be affected with side effects of blurred vision.
Suicidal Ideation
Antidepressants have been associated with increased suicidal thoughts early in treatment, especially in children and young adults. Associated symptoms include aggressiveness, motor restlessness, agitation, irritability, mania, anxiety and impulsivity. If these symptoms appear and the patient reports worsening depression, it is recommended that treatment should be discontinued or modified.
Motor Difficulties
Patients on effexor therapy also report problems with motor function. These effects include tremor, impaired coordination and balance and catatonic behavior. Many patients that experience these side effects choose to discontinue therapy due to effects on quality of life.
Cardiovascular Effects
Increased blood pressure, or hypertension, has been reported with effexor use and is related to the dose. It is recommended that patients on effexor have their blood pressure regularly monitored. In addition, increases in heart rate have also been reported that correlate to increasing dosage. Incidences of other cardiovascular effects such as disruptions in heart rhythm and changes seen on electrocardiogram have also been reported.
Sexual Dysfunction
Patients on effexor therapy occasionally report sexual dysfunction, which is a common reason to discontinue the drug. These include diminished libido, ejaculation dysfunction, impotence and disturbances with normal orgasm.
Gastrointestinal Symptoms
Problems with the gastrointestinal system are quite common with effexor therapy. Side effects include nausea, vomiting, decreased appetite, constipation and upset stomach. Patients tend to adapt to these side effects after several weeks of effexor therapy. In addition, patients have reported increased levels of cholesterol that are dependent on dose and duration of therapy.
Serotonin Syndrome
This is a dangerous side effect of all medications that affect levels of serotonin in the body. Symptoms include nausea, vomiting, sedation, sweating, altered consciousness, flushing of the face, shivering and increased blood pressure. If this occurs, effexor treatment should be discontinued and patient should consult a physician.
References
- "Massachusetts General Hospital Comprehensive Clinical Psychiatry, 1st Edition;" Stern; 2008
- Effexor (venlafaxine) package insert. Wyeth Pharmaceuticals, Inc.; 2005 Dec.
Member Comments