Generic name: venlafaxine [ ven-la-fax-een ]
Drug class: Serotonin-norepinephrine reuptake inhibitors
Availability: Prescription only
Pregnancy & Lactation: Risk data available
Brand names: Effexor
What is Venlafaxine?
Venlafaxine is used in adults to treat major depressive disorder. Venlafaxine extended-release (long-acting) capsules are also used to treat generalized anxiety disorder (GAD; excessive worrying that is difficult to control), social anxiety disorder (extreme fear of interacting with others or performing in front of others that interferes with normal life), and panic disorder (sudden, unexpected attacks of extreme fear and worry about these attacks).
Venlafaxine belongs to in a class of medications called selective serotonin and norepinephrine reuptake inhibitors (SNRIs). Venlafaxine works by increasing the amounts of serotonin and norepinephrine, natural substances in the brain that help maintain mental balance.
Warnings
You should not take venlafaxine if you have uncontrolled narrow-angle glaucoma.
Do not use venlafaxine within 7 days before or 14 days after you have used an MAO inhibitor, such as isocarboxazid, linezolid, methylene blue injection, phenelzine, or tranylcypromine.
Some young people have thoughts about suicide when first taking an antidepressant. Stay alert to changes in your mood or symptoms. Report any new or worsening symptoms to your doctor, such as: mood or behavioral changes, anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), more depressed, or have thoughts about suicide or hurting yourself.
Do not stop using venlafaxine without first talking to your doctor.
Do not give this medicine to anyone younger than 18 years old without the advice of a doctor. Venlafaxine is not FDA approved for use in children.
How should I take Venlafaxine
Take venlafaxine as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose.
Take with food at the same time each day.
Swallow the extended-release capsule or tablet whole and do not crush, chew, break, or open it.
If you cannot swallow a capsule whole, open it and mix the medicine with applesauce. Swallow the mixture right away without chewing.
Tell your doctor if you have any changes in sexual function, such as loss of interest in sex, trouble having an orgasm, or (in men) problems with erections or ejaculation. Some sexual problems can be treated.
Your symptoms may not improve for up to several weeks. Do not stop using venlafaxine suddenly, or you could have unpleasant symptoms (such as agitation, confusion, tingling or electric shock feelings). Ask your doctor before stopping the medicine.
Your blood pressure will need to be checked often.
This medicine may cause false results on a drug-screening urine test. Tell the laboratory staff that you use venlafaxine.
Store at room temperature away from moisture and heat.
Dosing information
Usual Adult Dose for Depression:
Immediate release:
-Initial dose: 37.5 mg orally twice a day OR 25 mg orally 3 times a day
-Maintenance dose: 75 to 150 mg orally per day, given in divided doses
-Maximum dose:
---Moderately depressed outpatients: 225 mg/day
---Severely depressed inpatients: 375 mg/day
Extended release:
-Initial dose: 75 mg orally once a day
-Maintenance dose: 75 to 225 mg orally once a day
-Maximum dose:
---Moderately depressed outpatients: 225 mg/day
---Severely depressed inpatients: 375 mg/day
Comments:
-The daily dosage of immediate-release formulations may be divided into 2 or 3 doses/day.
-Healthcare providers should consider initial extended release doses of 37.5 mg orally once a day for 4 to 7 days (before increasing the dose to 75 mg/day) in patients who may require additional time to adjust to the drug.
-Doses may be increased in daily increments of up to 75 mg orally at intervals of no less than 4 days.
-Patients should be periodically reassessed for the continued need of maintenance treatment and for the appropriate dose of treatment.
-Use of doses exceeding 225 mg/day is limited.
Usual Adult Dose for Generalized Anxiety Disorder:
Extended release:
-Initial dose: 75 mg orally once a day
-Maintenance dose: 75 to 225 mg orally once a day
-Maximum dose: 225 mg/day
Comments:
-Healthcare providers should consider initial extended release doses of 37.5 mg orally once a day for 4 to 7 days (before increasing the dose to 75 mg/day) in patients who may require additional time to adjust to the drug.
-Doses may be increased in daily increments of up to 75 mg orally at intervals of no less than 4 days.
Usual Adult Dose for Social Anxiety Disorder:
Extended release: 75 mg orally once a day
Comment: There is no evidence that doses greater than 75 mg/day confer additional benefit.
Usual Adult Dose for Panic Disorder:
Extended release:
-Initial dose: 37.5 mg orally once a day for 7 days, then 75 mg orally once a day thereafter
-Maintenance dose: 75 to 225 mg orally once a day
-Maximum dose: 225 mg/day
Comment: Doses may be increased in daily increments of 75 mg orally at intervals of no less than 7 days.
Before Taking
You should not take venlafaxine if you are allergic to it or to desvenlafaxine (Pristiq).
Do not use venlafaxine if you have used an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, methylene blue injection, phenelzine, and tranylcypromine.
Tell your doctor if you also use stimulant medicine, opioid medicine, herbal products, or medicine for depression, mental illness, Parkinson's disease, migraine headaches, serious infections, or prevention of nausea and vomiting. An interaction with venlafaxine could cause a serious condition called serotonin syndrome.
To make sure venlafaxine is safe for you, tell your doctor if you have ever had:
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bipolar disorder (manic depression);
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heart disease, high blood pressure, high cholesterol or triglycerides;
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diabetes;
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lung disease;
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glaucoma;
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a thyroid disorder;
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a seizure;
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sexual problems;
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bleeding problems;
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low blood levels of sodium; or
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liver or kidney disease.
Some young people may have increased suicidal thoughts when first starting a medicine to treat depression. Stay alert to changes in your mood or symptoms. Your family or caregivers should also watch for sudden changes in your behavior.
Taking this medicine during pregnancy could harm the baby, but stopping the medicine may not be safe for you. Do not start or stop venlafaxine without asking your doctor.
If you are pregnant, your name may be listed on a pregnancy registry to track the effects of venlafaxine on the baby.
Ask a doctor if it is safe to breastfeed while using this medicine.
What happens if I miss a dose?
Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.
What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.
What should I know about storage and disposal of this medication?
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).
It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org
Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.
What special dietary instructions should I follow?
Unless your doctor tells you otherwise, continue your normal diet.
What should I avoid while using Venlafaxine?
Do not drink alcohol.
Ask your doctor before taking a nonsteroidal anti-inflammatory drug (NSAID) such as aspirin, ibuprofen, naproxen, Advil, Aleve, Motrin, and others. Using an NSAID with venlafaxine may cause you to bruise or bleed easily.
Avoid driving or hazardous activity until you know how venlafaxine will affect you. Your reactions could be impaired.
Venlafaxine side effects
Get emergency medical help if you have signs of an allergic reaction to venlafaxine: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Tell your doctor right away if you have new or sudden changes in mood or behavior, including new or worse depression or anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, more active or talkative, or have thoughts about suicide or hurting yourself.
Venlafaxine may cause serious side effects. Call your doctor at once if you have:
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blurred vision, eye pain or redness, seeing halos around lights;
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cough, chest tightness, trouble breathing;
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a seizure (convulsions);
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unusual bleeding - nosebleeds, bleeding gums, abnormal vaginal bleeding, any bleeding that will not stop;
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low blood sodium - headache, confusion, problems with thinking or memory, weakness, feeling unsteady; or
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severe nervous system reaction - very stiff (rigid) muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, feeling like you might pass out.
Seek medical attention right away if you have symptoms of serotonin syndrome, such as: agitation, hallucinations, fever, sweating, shivering, fast heart rate, muscle stiffness, twitching, loss of coordination, nausea, vomiting, or diarrhea.
Common venlafaxine side effects may include:
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headache, dizziness, drowsiness, tiredness;
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ringing in your ears, feeling anxious, nervous, or jittery;
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sleep problems, unusual dreams;
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tremors;
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fast heartbeats;
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blurred vision;
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nausea, vomiting, diarrhea, constipation;
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changes in weight or appetite;
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dry mouth, yawning;
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increased sweating; or
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sexual problems.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
See more: Venlafaxine Side EffectsWhat other drugs will affect Venlafaxine?
Using venlafaxine with other drugs that make you drowsy can worsen this effect. Ask your doctor before using opioid medication, a sleeping pill, a muscle relaxer, or medicine for anxiety or seizures.
Tell your doctor about all your current medicines. Many drugs can affect venlafaxine, especially:
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any other antidepressant;
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amphetamines;
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fentanyl;
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cimetidine;
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tramadol;
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St. John's wort, tryptophan (sometimes called L-tryptophan);
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diet pills, weight loss medicine (such as phentermine);
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a blood thinner (warfarin, Coumadin, Jantoven);
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medicine to treat mood disorders, thought disorders, or mental illness - buspirone, lithium, and many others; or
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migraine headache medicine - sumatriptan, zolmitriptan, and others.
This list is not complete and many other drugs may interact with venlafaxine. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.
What other information should I know?
Keep all appointments with your doctor and the laboratory.
Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.