If you have depression or anxiety, your medical professional might recommend that you take a prescription drug called Effexor XR (venlafaxine extended release).

Effexor XR is used in adults to treat the conditions below:

Effexor XR contains the active drug venlafaxine. XR stands for extended release.

Effexor XR comes as a capsule that you swallow. The drug is used as a long-term treatment. If you’d like to learn more about Effexor XR, including specifics about its uses, you can see this overview of the medication.

As with other drugs, taking Effexor XR may cause side effects that can be mild or serious. For more information, we encourage you to continue reading.

While taking Effexor XR, mild or serious side effects may occur.

Here are some examples of side effects commonly reported with Effexor XR treatment:

These are just a few of the side effects that may occur with Effexor XR. We recommend that you read on to learn about other possible mild and serious side effects the drug may cause.

* To learn more about this side effect, you can see “Side effects up close” below.

You may experience mild side effects from Effexor XR.

Examples of mild side effects that have been reported with Effexor XR include:

* To learn more about this side effect, you can see “Side effects up close” below.

In most cases, the mild side effects of Effexor XR should be temporary. Some may be easily managed as well. But if you have any symptoms that continue or bother you, we encourage you to talk with your medical professional or pharmacist. Also, it’s important that you don’t stop using Effexor XR unless your medical professional recommends it.

It’s possible that Effexor XR can cause mild side effects other than those listed above. For more information, you can see the Effexor XR medication guide.

Note: After the Food and Drug Administration (FDA) approves a medication, it tracks and reviews side effects of the drug. If you’d like to notify the FDA about a side effect you’ve had with Effexor XR, you can visit MedWatch.

Although rare, Effexor XR may cause serious side effects.

Serious side effects that have been reported with Effexor XR include:

If you develop serious side effects while taking Effexor XR, it’s important to call your medical professional immediately. If you feel the side effects are life threatening or if you think you’re having a medical emergency, it’s vital to call 911 or your local emergency number right away.

* To learn more about this side effect, you can see “Side effects up close” below.
† An allergic reaction is possible after using Effexor XR. But this side effect wasn’t reported in studies.
Effexor XR has a boxed warning for this side effect. This is the most serious warning from the Food and Drug Administration (FDA). To learn more, you can refer to the “Side effects up close” section below.

Long-term side effects of Effexor XR

You may have long-term side effects with Effexor XR. But the length of time that side effects from the drug last can be different from person to person.

Most side effects of Effexor XR should ease within hours or days of taking the drug. But rarely, side effects of Effexor XR may last longer.

For example, lung problems* from Effexor XR may lead to longer-term health problems. And sexual side effects* from Effexor XR may last for several weeks or months after you stop taking the drug.

For more details about what to expect with Effexor XR treatment, we encourage you to talk with your medical professional.

* To learn more about this side effect, you can see the “Side effects up close” section below.

Below, we provide answers to some frequently asked questions about the side effects of Effexor XR.

What side effects of Effexor XR should I expect in the first week of treatment?

Certain side effects may be more common than others during your first week of Effexor XR treatment.

For example, the risk for suicidal thoughts and behaviors* with Effexor XR is highest right after starting treatment with the drug.

When you start using Effexor XR, your medical professional will prescribe you a low dosage of the drug. This helps lower your risk for side effects from Effexor XR. They may gradually increase your dosage over time until the symptoms of your condition have eased.

Most side effects of Effexor XR should go away within hours or days of taking the medication.

To learn more about possible side effects early on, we recommend talking with your medical professional or pharmacist.

* Effexor XR has a boxed warning for this risk. We explain more about this warning in the “Side effects up close” section below.

If I stop taking Effexor XR, could I have side effects of withdrawal?

Yes, you could have side effects of withdrawal if you suddenly stop taking Effexor XR.

Below are possible withdrawal symptoms of Effexor XR:

To lessen your risk for withdrawal symptoms, you should not stop taking Effexor XR until your medical professional advises you to do so. When they advise you to stop using the drug, they’ll help you safely and slowly lower your dosage over time.

If you have other questions about Effexor XR and withdrawal, we suggest that you talk with your medical professional or pharmacist.

Do the side effects of Effexor XR vary by strength and dose?

The side effects you have from Effexor XR can vary based on the strength or dose your medical professional prescribes.

For example, in studies of Effexor XR, greater increases in blood pressure occurred with higher doses of the drug.

Effexor XR comes as an oral capsule. The drug is available in the following strengths: 37.5 milligrams (mg), 75 mg, and 150 mg. To lower your risk for side effects, your medical professional typically won’t prescribe you a dosage higher than 225 mg per day.

If you have more questions about your risk for certain side effects from Effexor XR, we recommend talking with your medical professional.

Can missing a dose of Effexor XR cause any side effects?

Yes, you may have side effects from Effexor XR if you miss a dose of the drug.

For example, you may have withdrawal symptoms if you stop taking Effexor XR. For details, you can see the “If I stop taking Effexor XR, could I have side effects of withdrawal?” question above.

To learn more about Effexor XR and missed doses, we suggest talking with your medical professional or pharmacist.

Here’s some additional information about a few of the side effects Effexor XR may cause.

Weight gain or weight loss

Weight gain or weight loss may occur with Effexor XR. In studies of the drug, these side effects were rare.

Depression and anxiety, which Effexor XR is used to treat, can also cause weight changes. So you may gain or lose weight while you’re taking the drug because your condition is improving. This means weight changes may not be a side effect of Effexor XR itself.

Ways to help manage

If you’re concerned about weight gain or weight loss while taking Effexor XR, we recommend that you talk with your medical professional. They can suggest healthy ways for you to manage your weight.

Sexual side effects

Sexual side effects may occur with Effexor XR treatment. These side effects were common in studies of the drug.

Both males* and females* who took Effexor XR in studies of the drug had loss of libido (sex drive) as a side effect.

Males who used Effexor XR also reported other sexual side effects, including:

Females who took Effexor XR also reported not being able to have an orgasm.

Depression and anxiety, which Effexor XR is used to treat, can also cause sexual side effects. It may be hard to tell if these side effects are caused by the drug or the condition you’re using Effexor XR to treat.

* In this article, we use the terms “male” and “female” to refer to someone’s sex assigned at birth. For information about the difference between sex and gender, you can see this article.

Ways to help manage

We encourage you to talk with your medical professional about any sexual side effects you have with Effexor XR. They can help you figure out if the side effects are from the condition you’re using Effexor XR to treat or from the drug itself.

Lung problems

Effexor XR may cause lung problems. But this wasn’t a common side effect in studies of the drug.

Below are examples of possible lung problems with Effexor XR.

Ways to help manage

If you have any of the above symptoms while taking Effexor XR, it’s important to talk with your medical professional right away. They may test you to check for lung problems.

Allergic reaction

As with most drugs, Effexor XR can cause an allergic reaction in some people. But this side effect wasn’t reported in studies.

Symptoms of an allergic reaction can be mild or serious and can include:

  • skin rash
  • itchiness
  • flushing (temporary warmth, redness, or deepening of skin color)
  • swelling under your skin, typically in your eyelids, lips, hands, or feet
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

What might help

If you develop mild symptoms of an allergic reaction while using Effexor XR, such as itchiness, we recommend talking with your medical professional right away. (A mild reaction could become serious if it’s not treated.) They may suggest an over-the-counter product to help ease your symptoms.

If they confirm that you had a mild allergic reaction, they can advise you on whether it’s safe to keep taking the drug.

If you have symptoms of a severe allergic reaction, such as trouble breathing or swelling, it’s vital to call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your medical professional confirms that you had a serious allergic reaction, they may recommend you switch to a different treatment.

Suicidal thoughts and behaviors

Effexor XR has a boxed warning from the Food and Drug Administration (FDA) about suicidal thoughts and behaviors. The boxed warning appears on the drug’s label and alerts you to possible serious risks.

Drugs used to treat depression, such as Effexor XR, may increase the risk of suicidal thoughts and behaviors in people ages 24 and younger. This includes children, adolescents, and young adults. It’s important to note that Effexor XR isn’t approved for use in people younger than age 18.

If you’ve recently started taking Effexor XR or your medical professional recently changed your dosage, your risk for this side effect may be higher.

During your Effexor XR treatment, watch for the following symptoms:

Ways to help manage

If you have unusual changes in behaviors, moods, thoughts, or feelings while taking Effexor XR, you’re advised to talk with your medical professional right away. They may change your treatment plan or prescribe you a drug other than Effexor XR.

Suicide prevention

If you or someone you know is considering suicide, you’re not alone. Help is available right now:

Not in the U.S.? Find a helpline in your country with Befrienders Worldwide.

Monitoring side effects

While you take Effexor XR, you may want to write down information about any side effects you develop. You can share these notes with your medical professional. This is very helpful to do when you first take new medications or use multiple treatments.

In your notes, you can include answers to questions such as:

  • What dose was I taking when I developed the side effect?
  • How long after taking that dose did I have the side effect?
  • What symptoms did I develop?
  • How did the side effect impact my everyday activities?
  • What other medications was I also taking?
  • What other information do I think is important to share?

By writing down notes and sharing them with your medical professional, they’ll learn how Effexor XR affects you. They can use this information to adjust your treatment plan as needed.

It may not be safe to take Effexor XR if you have certain conditions. We describe these conditions and other considerations in more detail below.

FDA boxed warning: Suicidal thoughts and behaviors

Effexor XR has a boxed warning from the Food and Drug Administration (FDA). The warning appears on the drug’s label and alerts you to possible serious risks.

The boxed warning for Effexor XR is about suicidal thoughts and behaviors in children, adolescents, and young adults. It’s important to note that the drug isn’t approved for use in people younger than age 18.

For details, you can see the “Side effects up close” section above.

Other warnings

Effexor XR may not be right for you if you have certain medical conditions or other factors that affect your health. Talk with your medical professional about your health history before you take Effexor XR. The list below includes factors to consider.

Seizures. Seizures are a possible side effect of Effexor XR. Before taking the drug, tell your medical professional if you already have a condition that causes seizures. If you have such a condition, they may prescribe a treatment other than Effexor XR.

Bipolar disorder. Before taking Effexor XR, tell your medical professional if you have bipolar disorder. This is because the drug may cause mania or hypomania. If you have bipolar disorder, they’ll help determine if it’s safe for you to take Effexor XR.

Angle-closure glaucoma. Before starting Effexor XR treatment, be sure to tell your medical professional if you have angle-closure glaucoma. The drug can increase the risk for a glaucoma attack (sudden eye pain and blurry vision) in people who have this condition. If you have symptoms of a glaucoma attack while taking Effexor XR, it’s important to call 911 or your local emergency number right away.

High blood pressure. Effexor XR may cause high blood pressure. If you already have high blood pressure before taking Effexor XR, it’s recommended that you tell your medical professional. They’ll typically treat your high blood pressure before prescribing Effexor XR.

Liver or kidney problems. You may be at higher risk than usual for side effects from Effexor XR if you have liver or kidney problems. This is because these conditions can prevent your body from getting rid of Effexor XR. As a result, the level of Effexor XR may build up in your body, which can increase your risk for side effects.

Before taking Effexor XR, we recommend that you tell your medical professional about any liver or kidney problems you have. They may prescribe a lower dosage than usual of the drug.

Allergic reaction. If you’ve had an allergic reaction to Effexor XR or any of its ingredients, it’s important that you do not take this drug. You can ask your medical professional what other medications are better options for you.

Alcohol use and Effexor XR

It’s recommended that you avoid drinking alcohol while taking Effexor XR. This is because drinking alcohol while taking the medication may raise your risk for overdose.

If you drink alcohol, be sure to talk with your medical professional before starting treatment with Effexor XR. They can recommend safe ways to stop drinking. Or they may prescribe a different drug for you.

Pregnancy and breastfeeding while taking Effexor XR

It might not be safe to take Effexor XR while pregnant or breastfeeding.

For details about the risks and benefits of taking Effexor XR while pregnant or breastfeeding, we encourage you to talk with your medical professional.

It’s possible to misuse Effexor XR. Misuse refers to taking a drug in a way that’s different than how your medical professional recommended you take it.

However, studies of Effexor XR have shown a low risk for misuse of the drug.

It’s important that you take Effexor XR exactly as your medical professional prescribes it. During your treatment, they may assess you for signs of misuse from time to time.

Side effects can occur while taking Effexor XR, but they’re usually mild. Most lessen with time and won’t require treatment by a medical professional. But if you have questions about possible side effects from Effexor XR, it’s important to talk with your medical professional or pharmacist.

Here are a few suggestions to get you started:

  • Are there any side effects of Effexor XR that I should tell you about right away?
  • Does my age put me at a higher risk than usual for certain side effects from Effexor XR?
  • Am I taking any medications that might increase my risk for side effects from Effexor XR?

While you take Effexor XR, you may find it helpful to speak with a therapist or join a support group. You may also be interested in ways to afford therapy. The following articles might be helpful to you:

You can also visit the BetterHelp website to search for online counseling.

In addition, you can sign up for the Psych Central newsletter. We share stories from other people on mental health journeys as well as current information about treatments.

Disclaimer: Psych Centralhas 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 another 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.