- What is venlafaxine, and how does it work (mechanism of action)?
- What brand names are available for venlafaxine?
- Is venlafaxine available as a generic drug?
- Do I need a prescription for venlafaxine?
- What are the side effects of venlafaxine?
- What is the dosage for venlafaxine?
- Which drugs or supplements interact with venlafaxine?
- Is venlafaxine safe to take if I'm pregnant or breastfeeding?
- What else should I know about venlafaxine?
What is venlafaxine, and how does it work (mechanism of action)?
Venlafaxine is a selective serotonin and norepinephrine reuptake inhibitor (SNRI) used for treating depression. Other drugs in this class include milnacipran (Savella), duloxetine (Cymbalta), and desvenlafaxine (Pristiq). Venlafaxine affects neurotransmitters, the chemicals that nerves within the brain make and release in order to communicate with one another. Neurotransmitters either travel across the space between nerves, attach to receptors on the surface of nearby nerves, or they attach to receptors on the surface of the nerves that produced them, to be taken up by the nerve and released again (a process referred to as re-uptake).
Many experts believe that an imbalance among neurotransmitters is the cause of depression as well as other psychiatric disorders. Serotonin and norepinephrine are two neurotransmitters released by nerves in the brain. Venlafaxine works by preventing the reuptake of serotonin and epinephrine by nerves after they have been released. Since uptake is an important mechanism for removing released neurotransmitters and terminating their actions on adjacent nerves, the reduced uptake caused by venlafaxine increases the effect of serotonin and norepinephrine in the brain. Venlafaxine is available in an extended release formulation (Effexor XR). The FDA approved venlafaxine in December 1993.
What are the side effects of venlafaxine?
Venlafaxine, like most anti-depressants, can cause:
Other side effects that can occur are:
Increased blood pressure can occur, and blood pressure should be monitored.
Seizures have been reported.
The FDA suggests if anti-depressants are discontinued abruptly, symptoms may occur such as dizziness, headache, nausea, changes in mood, or changes in the sense of smell, taste, etc. (Such symptoms even may occur when even a few doses of anti-depressant are missed.) Therefore, it is generally recommended that the dose of anti-depressant be reduced gradually when therapy is discontinued.
Antidepressants increased the risk of suicidal thinking and behavior (suicidality) in short-term studies in children, adolescents, and young adults with depression and other psychiatric disorders. Anyone considering the use of venlafaxine or any other antidepressant in a child or adolescent must balance this risk with the clinical need. Patients who are started on therapy should be closely observed for clinical worsening, suicidality, or unusual changes in behavior.
Quick GuidePhysical Symptoms of Depression in Pictures
What is the dosage for venlafaxine?
Venlafaxine should be taken with food at doses specifically directed by a physician. Individual doses vary greatly among individuals. The anti-depressant effects are not maximal for 1-2 weeks. If discontinued, the dose of venlafaxine should gradually be reduced under the direction of a physician. For patients with difficulty swallowing tablets or capsules, capsules of Effexor XR can be opened and the contents sprinkled on a spoonful of applesauce but removal from the capsule allows immediate release of the drug so it is no longer an extended release drug.
The dose for treatment of depression using the immediate release formulation is 75 to 375 mg daily divided in 2 or 3 doses and given every 8 or 12 hours. The extended release dose is 37.5 mg to 225 mg once daily. Dosing is usually begun with low initial concentrations and adjusted as needed by the treating doctor.
Generalized anxiety and panic disorder are treated with 37.5 mg to 225 mg once daily using the extended release formulation. Social anxiety is treated with 75 mg daily using the extended release formulation.
Which drugs or supplements interact with venlafaxine?
Venlafaxine should not be used in combination with a monoamine oxidase inhibitor (MAOI) such as phenelzine (Nardil), tranylcypromine (Parnate), isocarboxazid (Marplan), and selegiline (Eldepryl), or within 14 days of discontinuing the MAOI. At least 5 days should be allowed after stopping venlafaxine before starting an MAOI. Combinations of SNRIs and MAOIs may lead to serious, sometimes fatal, reactions including very high body temperature, muscle rigidity, rapid fluctuations of heart rate and blood pressure, extreme agitation progressing to delirium, and coma. Similar reactions may occur if venlafaxine is combined with antipsychotics, tricyclic antidepressants or other drugs that affect serotonin in the brain. Examples include tryptophan, sumatriptan (Imitrex), lithium, linezolid (Zyvox), tramadol (Ultram), and St. John's Wort.
Combining venlafaxine with aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs), warfarin (Coumadin) or other drugs that are associated with bleeding may increase the risk of bleeding, because venlafaxine is associated with bleeding.
Most medications affecting the brain such as venlafaxine have the potential to slow reflexes or impair judgment. Therefore, caution is advised especially early in the course of treatment.
Safety has not been established in children below the age of 18 years.
Is venlafaxine safe to take if I'm pregnant or breastfeeding?
The effects of venlafaxine on the fetus during pregnancy are unknown.
It is not known if venlafaxine is secreted in breast milk, and therefore, if it may have an effect on nursing infants.
What else should I know about venlafaxine?
What preparations of venlafaxine are available?
- Tablets: 25, 37.5, 50, 75, and 100 mg.
- Tablets (Extended Release): 37.5, 75, 150, 225 mg;
- Capsules (Extended Release): 37.5, 75, and 150 mg.
How should I keep venlafaxine stored?
Store in a dry place at 20 C to 25 C (68 F to 77 F).
Venlafaxine (venlafaxine, Effexor XR [Effexor has been discontinued in the US]) is a drug in the class of drugs called SNRIs (serotonin and norepinephrine reuptake inhibitors) prescribed for the treatment of depression, depression with symptoms of anxiety, generalized anxiety disorder. Effexor XR is prescribed for the treatment of and panic disorder in adults. Side effects, drug interactions, dosage, and pregnancy safety information should be reviewed prior to taking this medication.
Multimedia: Slideshows, Images & Quizzes
Bipolar Disorder (Mania) Quiz: Test Your Emotional Wellness IQ
Who is at risk for developing bipolar disorder? Are you? Take this Bipolar Disorder Quiz to learn more about bipolar disorder, if...
Depression Quiz: Signs & Symptoms
Many people do not recognize the symptoms and warning signs of depression and depressive disorders in children and adults. With...
Panic Attacks (Panic Disorder) Quiz: Test Your Mental Health IQ
Could you suffer a panic attack? Take this Panic Attacks Quiz to learn causes, symptoms, and treatments for panic disorder. Use...
Learn to Spot Depression: Symptoms, Warning Signs, Medication
What is depression? Get information on symptoms, signs, tests, and treatments for many types of depression including major...
Depression Tips: Exercise, Diet, Stress Reduction, and More in Pictures
The right exercise, diet, and activities -- even playing with a pet --can help you recover from depression. Learn simple...
Schizophrenia: Symptoms, Types, Causes, Treatment
What is schizophrenia? Learn about schizophrenia symptoms, signs, and treatment. Read about schizophrenia types such as paranoid...
Depression Myths: Overwork, Recklessness and More in Pictures
Explore the myths and facts about depression. See how folk remedies and half-truths still prevent many from getting treatment for...
Anxiety Disorder Pictures: Symptoms, Panic Attacks, and More with Pictures
Learn about generalized anxiety disorder (GAD). See if your worries are normal or something more by learning about symptoms,...
Physical Symptoms of Depression in Pictures
Depression can cause physical problems such as insomnia, chest pain, fatigue, headaches, and more. Learn the signs of depression...
Healthy Aging: Sneaky Depression Triggers in Pictures
There are many causes and triggers of depression. From too little vitamin B12 to too much time alone, look at these surprising...
Depression Therapy: Myths, Facts, and More in Pictures
False ideas scare many depression suffers away from therapy and the quick relief and help these pros can provide. Let our experts...
Related Disease Conditions
People with bulimia nervosa, an eating disorder that involves episodes of bingeing and purging, experience symptoms and signs...
Depression is an illness that involves the body, mood, and thoughts and affects the way a person eats and sleeps, the way one...
Migraine headaches are severe headaches that are sensitive to light, sounds, and smells. Some people who suffer from...
Panic attacks are sudden feelings of terror that strike without warning. These episodes can occur at any time, even during sleep....
Posttraumatic Stress Disorder
Post-traumatic stress disorder (PTSD), a psychiatric condition, can develop after any catastrophic life event. Symptoms include...
Narcolepsy (Definition, Symptoms, Treatment, Medication)
Causes of narcolepsy, a chronic disease of the central nervous system, have not been fully determined. Some theories include...
Bipolar disorder (or manic depression) is a mental illness characterized by depression, mania, and severe mood swings. Treatment...
Obsessive Compulsive Disorder (OCD)
Obsessive compulsive disorder (OCD) is an anxiety disorder that causes a person to suffer repeated obsessions and compulsions....
Postpartum depression is a form of depression that occurs within a year after delivery. It is thought that rapid hormone changes...
Mental health is an optimal way of thinking, relating to others, and feeling. All of the diagnosable mental disorders fall under...
Neuropathic pain is a chronic condition that leads to ongoing pain symptoms. Patients can be predisposed to developing...
Depression in teenagers may be caused by many factors. Symptoms of teen depression include apathy, irresponsible behavior,...
Depression in the Elderly
Depression in the elderly is very common. That doesn't mean, though, it's normal. Treatment may involve antidepressants,...
Anxiety is a feeling of apprehension and fear characterized by symptoms such as trouble concentrating, headaches, sleep problems,...
Dysthymia is a less severe form of chronic depression. Symptoms and signs include insomnia, suicidal thoughts, guilt, empty...
Fragile X Syndrome
Fragile X syndrome is the most common inherited form of mental retardation. It's caused by a mutation on the X chromosome. People...
Hot Flashes (Causes, Symptoms & Medication Treatment in Men and Women)
Hot flashes (or flushing) is the most common symptom experienced by a woman prior to and during the early stages of menopause,...
Postherpetic neuralgia (PHN) is a painful complication of shingles. Symptoms include severe pain, itchy skin, and possible...
Schizotypal Personality Disorder
Schizotypal personality disorder is characterized by odd behaviors, feelings, perceptions, and ways of relating to others that...
Duck syndrome is a situation initially coined at Stanford University whereby a college student may seem to be calm on the surface...
Bipolar Disorder vs. Schizophrenia
Bipolar disorder and schizophrenia are mental illnesses that share some risk factors and treatments. Symptoms of bipolar disorder...
Treatment & Diagnosis
- Depression FAQs
- Panic Attacks Disorder FAQs
- Bipolar Disorder Mania FAQs
- Catherine Zeta-Jones: A Case of Bipolar II Disorder
- How To Reduce Your Medication Costs
- Pharmacy Visit, How To Get The Most Out of Your Visit
- Indications for Drugs: Approved vs. Non-approved
- Generic Drugs, Are They as Good as Brand-Names?
- Drugs: Buying Prescription Drugs Online Safely
- Drugs: The Most Common Medication Errors
- Medication Disposal - What to Do with Old or Unusable Medication
- Dangers of Mixing Medications
Medications & Supplements
Prevention & Wellness
- What Drugs Work Best for Diabetic Nerve Pain?
- 'Off-Label' Antidepressants Common, But Where's the Evidence?
- Study Questions Use of Antidepressants for Children, Teens
- Did Studies Lack Key Data on Link Between Antidepressants, Youth Suicides?
- Certain Antidepressants May Be Linked to Bipolar Disorder: Study
- This Treatment May Help Depression in Older People
- More Than Half of Women Have Hot Flashes for at Least 7 Years
- Weight Gain From Antidepressants Is Minimal, Study Suggests
- Antidepressant Eases Menopause-Related Symptoms, Study Finds
- Pfizer Recalls Effexor Antidepressant
- Antidepressants in Pregnancy Tied to Slight Risk of Lung Disorder in Babies
- Experts Lay Out Options for Menopause Symptoms
- Usual 'Hot Flash' Therapies Don't Help Prostate Cancer Patients: Study
- Antidepressants Aid Depressed Parkinson's Patients
- Menopause May Cost Women Sick Days
- Antidepressants May Not Raise Suicide Risk in Youth: Study
- Newer Antidepressants Work Equally Well, Study Finds
- Depression Rising, but Psychotherapy Declines
- Cataracts From Antidepressants?
Daily Health News
Subscribe to MedicineNet's Depression Newsletter
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
Top venlafaxine Related Articles
Bipolar DisorderBipolar disorder (or manic depression) is a mental illness characterized by depression, mania, and severe mood swings. Treatment may incorporate mood-stabilizer medications, antidepressants, and psychotherapy.
Bipolar Disorder QuizWho is at risk for developing bipolar disorder? Are you? Take this Bipolar Disorder Quiz to learn more about bipolar disorder, if you're at risk, and what you can do about it.
Bulimia NervosaPeople with bulimia nervosa, an eating disorder that involves episodes of bingeing and purging, experience symptoms and signs such as deteriorating teeth, sore throat, constipation, thinning hair, and dehydration. Treatment of bulimia may involve cognitive behavior therapy, family therapy, nutritional counseling, and medication.
DepressionDepression is an illness that involves the body, mood, and thoughts and affects the way a person eats and sleeps, the way one feels about oneself, and the way one thinks about things. The principal types of depression are major depression, dysthymia, and bipolar disease (also called manic-depressive disease).
Depression SlideshowWhat is depression? Get information on symptoms, signs, tests, and treatments for many types of depression including major depression, chronic depression, teen depression, and postpartum depression.
Depression QuizMany people do not recognize the symptoms and warning signs of depression and depressive disorders in children and adults. With proper diagnosis, treatments and medications are available. Take this quiz to learn more about recovery from depression.
Depression Tips SlidesThe right exercise, diet, and activities -- even playing with a pet --can help you recover from depression. Learn simple lifestyle changes you can do to improve your mood.
Mental Health (Psychology)Mental health is an optimal way of thinking, relating to others, and feeling. All of the diagnosable mental disorders fall under the umbrella of mental illness. Depression, anxiety, and substance-abuse disorders are common types of mental illness. Symptoms and signs of mental illness include irritability, moodiness, insomnia, headaches, and sadness. Treatment may involve psychotherapy and medication.
Migraine headaches are severe headaches that are sensitive to light, sounds, and smells. Some people who suffer from migraines also have severe head pain. People also have symptoms of nausea and vomiting. Common migraine triggers may include:
- Certain foods
- Changes in barometric pressure
- Other phenomenon
They are diagnosed by a doctor if the headache pattern fits established migraine headache criteria. Over-the-counter (OTC) and prescription medications are sometime used to treat acute migraines. To prevent or reduce the frequency and severity of them doctors recommend supplements and prescription medications, for example:
- Blood pressure drugs
- Anti-seizure drugs
Lifestyle modification helps in migraine management. Many people who suffer from migraines get relief from their condition by keeping a headache diary, identifying and avoiding triggers, and taking appropriate medication.
Myths and Facts About Depression SlideshowExplore the myths and facts about depression. See how folk remedies and half-truths still prevent many from getting treatment for depression. Learn about the unusual symptoms and many ways to recover from depression.
NarcolepsyCauses of narcolepsy, a chronic disease of the central nervous system, have not been fully determined. Some theories include abnormalities in hypocretin neurons in the brain or an autoimmune disorder. Symptoms of narcolepsy include:
- excessive daytime sleepiness,
- hypnagogic hallucinations,
- sleep paralysis,
- disturbed nocturnal sleep, and
- automatic behavior.
Diagnosis of narcolepsy is based on a clinical evaluation, specific questionnaires, sleep logs or diaries, and the results of sleep laboratory tests. Treatments of narcolepsy symptoms include medication and lifestyle changes.
Obsessive Compulsive Disorder (OCD)Obsessive compulsive disorder (OCD) is an anxiety disorder that causes a person to suffer repeated obsessions and compulsions. Symptoms include irresistible impulses despite a person's realization that the thoughts are irrational, excessive hand washing, skin picking, lock checking, or repeatedly rearranging items. People with OCD are more likely to develop trichotillomania, muscle or vocal tics, or an eating disorder. Treatment for OCD includes psychotherapy, behavioral therapy, and medication.
Panic Attacks QuizCould you suffer a panic attack? Take this Panic Attacks Quiz to learn causes, symptoms, and treatments for panic disorder. Use this quiz to learn to recognize the main elements of this serious, yet common disorder known as panic attacks.
Panic DisorderPanic attacks are sudden feelings of terror that strike without warning. These episodes can occur at any time, even during sleep. A person experiencing a panic attack may believe that he or she is having a heart attack or that death is imminent. The fear and terror that a person experiences during a panic attack are not in proportion to the true situation and may be unrelated to what is happening around them. Most people with panic attacks experience several of the following symptoms: racing heartbeat, faintness, dizziness, numbness or tingling in the hands and fingers, chills, chest pains, difficulty breathing, and a feeling of loss or control. There are several treatments for panic attacks.
Postpartum DepressionPostpartum depression is a form of depression that occurs within a year after delivery. It is thought that rapid hormone changes after childbirth may lead to depression. Symptoms of postpartum depression include crying a lot, headaches, chest pains, eating too little or too much, sleeping too little or too much, withdrawal from friends and family, and feeling irritable, sad, hopeless, worthless, guilty, and overwhelmed. Treatment typically involves talk therapy and medication.
Posttraumatic Stress DisorderPost-traumatic stress disorder (PTSD), a psychiatric condition, can develop after any catastrophic life event. Symptoms include nightmares, flashbacks, sweating, rapid heart rate, detachment, amnesia, sleep problems, irritability, and exaggerated startle response. Treatment may involve psychotherapy, group support, and medication.
Schizophrenia SlideshowWhat is schizophrenia? Learn about schizophrenia symptoms, signs, and treatment. Read about schizophrenia types such as paranoid schizophrenia, catatonic schizophrenia, and disorganized schizophrenia.