Highlights for venlafaxine
- Venlafaxine oral tablet is only available as a generic drug. It comes in both an immediate-release and an extended-release form.
- Venlafaxine also comes as an extended-release oral capsule.
- Venlafaxine oral tablet is used to treat depression (immediate-release tablet and extended-release tablet). It’s also used to treat social anxiety disorder (extended-release tablet only).
FDA warning: Suicidal behavior warning
- This drug has a black box warning. This is the most serious warning from the Food and Drug Administration (FDA). A black box warning alerts doctors and patients about drug effects that may be dangerous.
- Venlafaxine may increase suicidal thoughts or actions in some children and young adults. This usually happens within the first few months of treatment or during dosage changes. Call your doctor right away if you notice new or sudden changes in your or your child’s mood, behavior, thoughts, or feelings, especially if they are severe.
- Incorrect drug screening results warning: This drug may interfere with the results of urine tests for some illegal drugs, including phencyclidine (PCP) and amphetamine. It may make these test results positive even when you haven’t used the illegal drugs. This effect may last for several days after you stop taking venlafaxine.
- High blood pressure warning: Venlafaxine may increase your blood pressure. Your doctor will likely make sure your blood pressure is normal before you start taking venlafaxine. They will check your blood pressure regularly during your treatment.
What is venlafaxine?
Venlafaxine is a prescription drug. It comes as an oral tablet and an oral capsule.
Venlafaxine oral tablet comes in immediate-release and extended-release forms. Both forms are only available as generic drugs. Generic drugs usually cost less than brand-name drugs.
Why it’s used
Venlafaxine may be used as part of a combination therapy. This means you may need to take it with other medications to treat your condition.
How it works
Venlafaxine belongs to a class of antidepressant drugs called serotonin norepinephrine reuptake inhibitors (SNRIs). A class of drugs is a group of medications that work in a similar way. These drugs are often used to treat similar conditions.
SNRIs work by increasing the levels of substances called serotonin and norepinephrine in your brain. Having more serotonin and norepinephrine in your brain can improve your symptoms of depression and anxiety.
Venlafaxine side effects
Venlafaxine oral tablet may cause drowsiness. It may also affect your ability to make decisions, think clearly, or react quickly. You should not drive, use heavy machinery, or do things that require you to be alert until you know you can function normally. Venlafaxine may also cause other side effects.
More common side effects
The more common side effects of venlafaxine can include:
- unusual dreams
- sexual problems, such as:
- decreased interest in sex
- impotence (not being able to get or keep an erection)
- trouble having an orgasm
- loss of appetite
- nausea or vomiting
- dry mouth
- trouble sleeping or change in sleep habits
- tremor or shaking
- blurry vision
- feeling anxious, nervous, or jittery
- increased heart rate
If these effects are mild, they may go away within a few days or a couple of weeks. If they’re more severe or don’t go away, talk to your doctor or pharmacist.
Serious side effects
Call your doctor right away if you have serious side effects. Call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency. Serious side effects and their symptoms can include the following:
- Attempting suicide
- Acting on dangerous impulses
- Aggressive or violent behavior
- Thoughts about suicide or dying
- New or worsened depression
- New or worsened anxiety or panic attacks
- Agitation, restlessness, anger, or irritability
- Trouble sleeping
- Serotonin syndrome. Symptoms can include:
- hallucinations (seeing or hearing something that isn’t there)
- changes in your mental status
- coordination problems
- muscle twitching or overactive reflexes
- fast heart rate
- high or low blood pressure
- muscle stiffness
- High blood pressure. Symptoms can include:
- chest pain
- Mania. Symptoms can include:
- greatly increased energy
- severe trouble sleeping
- racing thoughts
- reckless behavior
- unusually grand ideas
- excessive happiness or irritability
- talking more or faster than usual
- Eye problems. Symptoms can include:
- eye pain
- vision changes
- enlarged pupils
- swelling or redness in or around your eyes
- Low sodium levels. Symptoms can include:
- feeling unsteady
- problems concentrating
- thinking or memory problems
- Bruising easily
- Frequent nosebleeds
- Frequent bleeding from your gums while brushing your teeth or flossing
- Dark, tar-like stool
- Bleeding from wounds that’s hard to stop
- Lung disease or pneumonia. Symptoms can include:
- shortness of breath that gets worse
- chest discomfort
Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs affect each person differently, we cannot guarantee that this information includes all possible side effects. This information is not a substitute for medical advice. Always discuss possible side effects with a healthcare provider who knows your medical history.
Venlafaxine may interact with other medications
Venlafaxine oral tablet can interact with other medications, vitamins, or herbs you may be taking. An interaction is when a substance changes the way a drug works. This can be harmful or prevent the drug from working well.
To help avoid interactions, your doctor should manage all of your medications carefully. Be sure to tell your doctor about all medications, vitamins, or herbs you’re taking. To find out how this drug might interact with something else you’re taking, talk to your doctor or pharmacist.
Examples of drugs that can cause interactions with venlafaxine are listed below.
Drugs you should not use with venlafaxine
Do not take these drugs with venlafaxine. When used with venlafaxine, these drugs can cause dangerous effects in your body. Examples of these drugs include:
- Monoamine oxidase inhibitors (MAOIs), including linezolid and methylene blue. Unless directed by your doctor, do not start venlafaxine within 2 weeks of stopping an MAOI and do not take an MAOI within 7 days of stopping venlafaxine. Taking venlafaxine and an MAOI too close together in time may cause serious or life-threatening side effects. These side effects can include high fever, uncontrolled muscle spasms, and stiff muscles. Other side effects can include sudden changes in your heart rate or blood pressure, confusion, and passing out.
- Drugs for weight loss, such as phentermine. Using venlafaxine with drugs such as phentermine may lead to excessive weight loss, serotonin syndrome, and heart problems such as rapid heart rate and high blood pressure.
Interactions that increase your risk of side effects
Taking venlafaxine with certain medications raises your risk of side effects. Examples of these drugs include:
- Cimetidine. Taking this drug with venlafaxine raises your risk of high blood pressure or liver disease. These risks are greater if you are a senior.
- Haloperidol. Taking this drug with venlafaxine raises your risk of QT prolongation. This is a heart condition with symptoms such as dizziness and an irregular heart rhythm.
- Warfarin. Taking this drug with venlafaxine raises your risk of bleeding. Your doctor will monitor you closely, especially when starting or stopping your venlafaxine therapy. Tell your doctor right away if you notice any abnormal bleeding or bruising.
- Anti-inflammatory drugs such as aspirin, ibuprofen, naproxen, and ketoprofen. Taking any of these drugs with venlafaxine raises your risk of bleeding. Your doctor will monitor you closely, especially when starting or stopping your venlafaxine therapy. Tell your doctor right away if you notice any abnormal bleeding or bruising.
- Drugs such as ritonavir, clarithromycin, or ketoconazole. Drugs such as ritonavir, clarithromycin, or ketoconazole can slow the breakdown of drugs in your body. If you take any of these drugs with venlafaxine, the amount of venlafaxine may build up in your body. This would increase your risk of side effects.
- Drugs that cause drowsiness, such as zolpidem, lorazepam, and diphenhydramine. Taking any of these drugs with venlafaxine may make the sleepiness from venlafaxine even worse.
- Other drugs that can increase serotonin levels, such as fluoxetine, paroxetine, citalopram, duloxetine, lithium, and tramadol. Venlafaxine increases your levels of serotonin. Taking it with any of these drugs may increase your serotonin levels even more. If your serotonin levels are too high, a life-threatening condition called serotonin syndrome can occur. Your doctor will monitor you closely when starting or increasing your dosage of either drug.
- Certain drugs for migraine, called triptans, such as sumatriptan, rizatriptan, and zolmitriptan. Venlafaxine increases your levels of serotonin. Taking it with any of these drugs may increase your serotonin levels even more. If your serotonin levels are too high, a life-threatening condition called serotonin syndrome can occur. Your doctor will monitor you closely when starting or increasing your dosage of either drug.
Interactions that can make your drugs less effective
When certain drugs are used with venlafaxine, they may not work as well. This is because the amount of these drugs in your body may be decreased. Examples of these drugs include:
- Metoprolol. Metoprolol may be less effective when you take it with venlafaxine. This may cause your blood pressure to rise. Talk to your doctor before taking these drugs together.
Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs interact differently in each person, we cannot guarantee that this information includes all possible interactions. This information is not a substitute for medical advice. Always speak with your healthcare provider about possible interactions with all prescription drugs, vitamins, herbs and supplements, and over-the-counter drugs that you are taking.
Venlafaxine oral tablet comes with several warnings.
Venlafaxine can cause a severe allergic reaction. Symptoms can include:
- trouble breathing
- swelling of your face, tongue, eyes, or mouth
- rash, hives, or blisters, alone or with joint paint or fever
If you have an allergic reaction, call your doctor or local poison control center right away. If your symptoms are severe, call 911 or go to the nearest emergency room.
Don’t take this drug again if you’ve ever had an allergic reaction to it. Taking it again could be fatal (cause death).
Alcohol interaction warning
Do not drink alcohol with venlafaxine. Drinking alcohol raises your risk of sleepiness from venlafaxine. This may affect your ability to make decisions, think clearly, and react quickly. If you drink alcohol, talk to your doctor.
Warnings for people with certain health conditions
For people with liver disease: If you have a history of liver disease, your liver may not process this drug as quickly as it should. This could lead to a buildup of this drug in your body. Your doctor may start you on a reduced dosage. If they increase your dosage later, they will monitor you closely.
For people with kidney disease: If you have kidney disease or a history of kidney disease, you may not be able to clear this drug from your body well. This may increase the levels of venlafaxine in your body. This can cause more side effects. Your doctor may start you on a low dosage and monitor you closely if they increase your dosage.
For people with heart problems: Venlafaxine can increase your heart rate, especially if you’re taking doses greater than 200 mg per day. If you have heart failure or if you’ve recently had a heart attack, your heart may not be able to tolerate this side effect.
For people with hyperthyroidism: Hyperthyroidism can increase your heart rate. Venlafaxine can also increase your heart rate. If you have hyperthyroidism and take venlafaxine, your heart rate may increase to a dangerous level. You are especially at risk if you take venlafaxine doses greater than 200 mg per day.
For people with a history of seizures: Venlafaxine raises your risk of seizures. If you have a seizure, stop taking venlafaxine and call your doctor right away.
For people with increased eye pressure (glaucoma): Venlafaxine can widen your pupils and block the flow of fluid in your eye. These effects can increase the pressure in your eyes. People with a history of increased eye pressure or glaucoma should have their eye pressure checked regularly while taking venlafaxine. Do not take venlafaxine if you have uncontrolled angle-closure glaucoma.
Warnings for other groups
For pregnant women: Venlafaxine is a category C pregnancy drug. That means two things:
- Research in animals has shown adverse effects to the fetus when the mother takes the drug.
- There haven’t been enough studies done in humans to be certain how the drug might affect the fetus.
Talk to your doctor if you’re pregnant or plan to become pregnant. This drug should only be used if the potential benefit justifies the potential risk to the fetus. Call your doctor right away if you become pregnant while taking this drug.
For women who are breastfeeding: Venlafaxine may pass into breast milk and cause side effects in a child who is breastfed. Talk to your doctor about breastfeeding your child. You may need to decide whether to stop breastfeeding or stop taking this medication.
For seniors: The kidneys of older adults may not work as well as they used to. This can cause your body to process drugs more slowly. As a result, more of a drug stays in your body for a longer time. This raises your risk of side effects. Older adults may be at higher risk than younger people for low sodium levels in their blood when taking venlafaxine.
For children: This drug should not be used in people younger than 18 years of age.
How to take venlafaxine
All possible dosages and drug forms may not be included here. Your dosage, drug form, and how often you take the drug will depend on:
- your age
- the condition being treated
- how severe your condition is
- other medical conditions you have
- how you react to the first dose
Forms and strengths
- Form: immediate-release oral tablet
- Strengths: 25 mg, 37.5 mg, 50 mg, 75 mg, 100 mg
- Form: extended-release oral tablet
- Strengths: 37.5 mg, 75 mg, 150 mg, 225 mg
Dosage for depression
Adult dosage (ages 18 years and older)
- Immediate-release oral tablets:
- Typical starting dosage: 75 mg total per day, taken in two or three divided doses
- Dosage increases: If needed, your doctor may increase your dosage to 150 mg per day.
- Typical maximum dosage: 225 mg per day. If you have more severe depression, your doctor may prescribe a dosage as high as 375 mg per day, taken in three divided doses.
- Extended-release oral tablets:
- Typical starting dosage: 75 mg per day, taken in a single dose in the morning or evening. Some patients should start at a lower dosage of 37.5 mg per day for 4–7 days.
- Dosage increases: If needed, your doctor may increase your dosage. They may increase it every 4 days by 75 mg until you reach 225 mg per day.
- Typical maximum dosage: 225 mg per day.
Child dosage (ages 0–17 years)
This medication should not be used in people younger than 18 years of age.
Dosage for social anxiety disorder
Adult dosage (ages 18 years and older)
Extended-release oral tablets:
- Typical dosage: 75 mg per day, given in a single dose in the morning or evening.
- Maximum dosage: 75 mg per day.
Child dosage (ages 0–17 years)
This medication should not be used in people younger than 18 years of age.
Special dosage considerations
People with liver problems: People with mild to moderate liver problems should take about half of the typical dose. People with severe liver disease or cirrhosis may need an even lower dosage. Your doctor can tell you more.
People with kidney problems: People with mild to moderate kidney problems should take 75% of the typical dosage. People who are on dialysis should take half of the typical dosage. Your doctor can tell you more.
Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs affect each person differently, we cannot guarantee that this list includes all possible dosages. This information is not a substitute for medical advice. Always to speak with your doctor or pharmacist about dosages that are right for you.
Take as directed
Venlafaxine oral tablet is used for long-term treatment. It comes with serious risks if you don’t take it as prescribed.
If you stop taking the drug suddenly or don’t take it at all: Your depression or anxiety may not get better and may get worse. Do not stop venlafaxine without talking to your doctor. Stopping venlafaxine too quickly can cause serious symptoms such as:
- trouble sleeping
- tingling or “pins and needles” feeling
If this happens, your doctor may have you start taking venlafaxine again and decrease your dosage slowly.
If you miss doses or don’t take the drug on schedule: Your medication may not work as well or may stop working completely. For this drug to work well, a certain amount needs to be in your body at all times.
If you take too much: You could have dangerous levels of the drug in your body. This can lead to death. Symptoms of an overdose of this drug can include:
- fast heart rate
- unusual sleepiness
- enlarged pupils
- heart rhythm changes
- low blood pressure
- muscle aches or pains
If you think you’ve taken too much of this drug, call your doctor or seek guidance from the American Association of Poison Control Centers at 800-222-1222 or through their online tool. But if your symptoms are severe, call 911 or go to the nearest emergency room right away.
What to do if you miss a dose: Take your dose as soon as you remember. If you remember just a few hours before your next scheduled dose, take only one dose. Never try to catch up by taking two doses at once. This could result in dangerous side effects.
How to tell if the drug is working: The symptoms of your depression or anxiety should be less severe or happen less often.
Important considerations for taking venlafaxine
Keep these considerations in mind if your doctor prescribes venlafaxine oral tablet for you.
- Take venlafaxine with food.
- You can cut or crush the immediate-release tablet, but do not cut or crush the extended-release tablet.
- Store the immediate-release oral tablet at room temperature between 68°F and 77°F (20°C and 25°C).
- Store the extended-release oral tablet at temperatures between 59°F and 86°F (15°C and 30°C).
- Keep this drug away from light.
- Don’t store this medication in moist or damp areas, such as bathrooms.
A prescription for this medication is refillable. You should not need a new prescription for this medication to be refilled. Your doctor will write the number of refills authorized on your prescription.
When traveling with your medication:
- Always carry your medication with you. When flying, never put it into a checked bag. Keep it in your carry-on bag.
- Don’t worry about airport X-ray machines. They can’t hurt your medication.
- You may need to show airport staff the pharmacy label for your medication. Always carry the original prescription-labeled container with you.
- Don’t put this medication in your car’s glove compartment or leave it in the car. Be sure to avoid doing this when the weather is very hot or very cold.
Not every pharmacy stocks this drug. When filling your prescription, be sure to call ahead to make sure your pharmacy carries it.
Many insurance companies require a prior authorization for this drug. This means your doctor may need to get approval from your insurance company before your insurance company will pay for the prescription.
Are there any alternatives?
There are other drugs available to treat your condition. Some may be better suited for you than others. Talk to your doctor about other drug options that may work for you.
Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up-to-date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or other healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.