Effexor XR (venlafaxine extended-release) is a brand-name extended-release capsule. It’s prescribed for certain mental health conditions. As with other drugs, Effexor XR can cause side effects. This includes the risk of suicidal thoughts and behaviors.

Effexor XR can cause certain side effects, some of which are more common than others. These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

These are just a few of the more common side effects reported by people who took Effexor XR in clinical trials:

* For more information about this side effect, see “Side effect specifics” below.

Mild side effects can occur with Effexor XR use. This list doesn’t include all possible mild side effects of the drug. For more information, you can refer to Effexor XR’s prescribing information.

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

These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. If you develop a side effect while taking Effexor XR and want to tell the FDA about it, visit MedWatch.

* For more information about this side effect, see “Side effect specifics” below.
† An allergic reaction is possible after taking Effexor XR. However, this side effect wasn’t reported in clinical trials. To learn more, see the “Side effect specifics” section below.

Effexor XR may cause serious side effects. The list below may not include all possible serious side effects of the drug. For more information, you can refer to Effexor XR’s prescribing information.

If you develop serious side effects while taking Effexor XR, call your doctor right away. If the side effects seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Serious side effects that have been reported and their symptoms include:

* Effexor XR has a boxed warning for this side effect. This is a serious warning from the Food and Drug Administration (FDA). To learn more, see the “Side effect specifics” section below.
† An allergic reaction is possible after taking Effexor XR. However, this side effect wasn’t reported in clinical trials. To learn more, see the “Side effect specifics” section below.

Effexor XR is not approved for use in children. However, doctors may prescribe Effexor XR off-label for certain conditions in people ages 18 years and younger. With off-label use, doctors prescribe a drug for a condition it’s not approved to treat.

Many of Effexor XR’s side effects in children are expected to be the same as for adults. However, certain side effects may be more common in children than in adults. A few examples include weight loss and loss of appetite.

In addition, in clinical trials of Effexor XR, certain side effects were only reported in children taking Effexor XR. These side effects weren’t reported in adults. Some examples include muscle pain, abdominal pain, and indigestion.

For more information about Effexor XR’s side effects in children, talk with your child’s doctor or pharmacist.

Effexor XR may cause several side effects. Here are some frequently asked questions about the drug’s side effects and their answers.

Will I experience certain side effects during the first week of treatment with Effexor XR?

Yes, it’s possible. Certain side effects of Effexor XR may be more likely than others during the first week of treatment.

For example, the risk of suicidal thoughts and behaviors* with Effexor XR is highest during the first few weeks and months of treatment.

Your doctor will start by prescribing a low Effexor XR dosage. This helps reduce your risk of side effects from the drug. Your doctor may gradually increase your dosage over time until the symptoms of your condition have eased. For more details about the dosage of Effexor XR, see this article.

If you have other questions about what to expect with Effexor XR, talk with your doctor or pharmacist.

* Effexor XR has a boxed warning for this side effect. This is a serious warning from the Food and Drug Administration (FDA). To learn more, see the “Side effect specifics” section below.

Can Effexor XR cause long-term side effects?

It’s possible for Effexor XR to cause certain long-term side effects.

For example, stopping Effexor XR after taking the drug long-term may lead to withdrawal symptoms. These are side effects that can happen when you stop taking a drug your body is used to. Examples of these symptoms include:

Due to this risk, it’s important to talk with your doctor before stopping Effexor XR treatment. If they tell you it’s safe to stop the drug, they’ll slowly lower your Effexor XR dosage over time. This will reduce the risk of withdrawal symptoms. Your doctor can tell you whether a different treatment can be prescribed for your condition.

Although rare, Effexor XR may also cause lung problems, such as interstitial lung disease. Lung problems may begin during treatment but could lead to long-term complications that continue after stopping Effexor XR.

If you have questions about the risk of long-term side effects with Effexor XR, talk with your doctor or pharmacist.

Learn more about some of the side effects that Effexor XR may cause. To find out how often side effects occurred in clinical trials, see the prescribing information for Effexor XR.

Risk of suicidal thoughts and behaviors

Effexor XR has a boxed warning about the risk of suicidal thoughts and behaviors. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). It lets doctors and patients know about a drug’s effects that may be dangerous.

Taking antidepressants, such as Effexor XR, may increase the risk of suicidal thoughts and behaviors. This risk may be highest in children and adults ages 24 years and younger. Keep in mind that Effexor XR is not approved for use in children.

Suicidal thoughts and behaviors were not reported in adults taking Effexor XR in clinical trials. However, there were rare reports of this side effect in children, adolescents, and young adults.

Doctors will monitor for suicidal thoughts and behaviors in people of any age taking Effexor XR. They’ll watch most closely during the first few months of treatment and whenever they adjust your Effexor XR dosage.

Symptoms your doctor may watch for include:

  • mood changes, such as anger, irritability, or agitation
  • feelings of isolation or hopelessness
  • loss of interest in activities you used to enjoy
  • sleeping more or less frequently than usual
  • thoughts of harming yourself or ending your life

What you can do

While you’re taking Effexor, tell your doctor right away if you have any of the symptoms above. If you have thoughts of harming yourself or ending your life, you can also contact the Suicide and Crisis Lifeline at 988.

Dry mouth

Dry mouth was a common side effect in clinical trials of Effexor XR.

With dry mouth, you may notice cracked lips, sticky saliva, or bad breath.

What you can do

If you have bothersome or long lasting dry mouth with Effexor XR, talk with your doctor. They can recommend ways to ease this side effect. Examples include:

  • sipping water frequently throughout the day
  • chewing sugar-free gum or sucking on hard candies
  • using an alcohol-free mouth rinse
  • limiting salt intake

You can also view this article for useful tips on managing dry mouth.

Allergic reaction

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

Symptoms can be mild or serious and can include:

  • skin rash
  • itching
  • flushing
  • 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 you can do

For mild symptoms of an allergic reaction, call your doctor right away. They may recommend ways to ease your symptoms and determine whether you should keep taking Effexor XR. However, if your symptoms are serious and you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Suicide prevention

If you know someone at immediate risk of self-harm, suicide, or hurting another person:

  • Ask the tough question: “Are you considering suicide?”
  • Listen to the person without judgment.
  • Call 911 or the local emergency number, or text TALK to 741741 to communicate with a trained crisis counselor.
  • Stay with the person until professional help arrives.
  • Try to remove any weapons, medications, or other potentially harmful objects if it’s safe to do so.

If you or someone you know is having thoughts of suicide, a prevention hotline can help. The 988 Suicide and Crisis Lifeline is available 24 hours a day at 988. During a crisis, people who are hard of hearing can use their preferred relay service or dial 711 then 988.

Find more links and local resources.

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Keep reading to learn more about precautions for Effexor XR.

Boxed warning: Risk of suicidal thoughts and behaviors

This drug has a boxed warning for the risk of suicidal thoughts and behaviors. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). For details, see the “Side effect specifics” section above.

Other precautions

Be sure to talk with your doctor about your health history before you take Effexor XR. This drug may not be the right treatment for you if you have certain medical conditions or other factors that affect your health. These are considered drug-condition or drug-factor interactions. The conditions and factors to consider include:

Angle-closure glaucoma. Before starting Effexor XR treatment, tell your doctor if you have angle-closure glaucoma. Effexor XR may cause dilated pupils, which could lead to acute close-angle glaucoma in people with narrow eye angles. This condition is a medical emergency that can lead to permanent vision loss. Your doctor may recommend getting an eye exam before taking Effexor XR.

High blood pressure. If you have high blood pressure, tell your doctor before starting Effexor XR treatment. This drug may cause high blood pressure. If you already have this condition, Effexor XR could cause it to become worse. Your doctor will likely make sure your high blood pressure is treated before prescribing Effexor XR.

Seizure. Effexor XR may increase the risk of seizure in people who have a seizure disorder, such as epilepsy. Before taking Effexor XR, tell your doctor if you have a seizure disorder. They can recommend whether Effexor XR is safe to take.

Kidney or liver problems. Having a kidney or liver problem could increase your risk of side effects with Effexor XR. Due to this risk, doctors will typically prescribe a lower dosage of Effexor XR if you have a kidney or liver problem. If you have either condition, tell your doctor before taking Effexor XR.

Bipolar disorder, hypomania, or mania. Effexor XR may increase the risk of hypomania or mania in people who’ve had either condition in the past. The risk is also higher in people with bipolar disorder. Before taking Effexor XR, talk with your doctor about your history of mental health conditions. They can tell you whether Effexor XR is a safe treatment option.

Allergic reaction. If you’ve had an allergic reaction to Effexor XR or any of its ingredients, your doctor will likely not prescribe Effexor XR. Ask your doctor what other medications may be better options for you.

Pregnancy or breastfeeding. If you’re pregnant or breastfeeding your child, talk with your doctor before starting treatment with Effexor XR. This drug may not be safe for you to take. You and your doctor can discuss the risks and benefits of taking this drug during pregnancy or while breastfeeding.

If you’re prescribed Effexor XR during pregnancy, consider enrolling in a pregnancy registry. These registries help collect information about the safety of medications, including Effexor XR, during pregnancy. To learn more, talk with your doctor. You can also visit this registry website or call 844-405-6185.

Alcohol consumption. If you drink alcohol, Effexor XR may not be safe for you to take. Drinking alcohol while taking the drug may increase the risk of sleepiness and overdose with Effexor XR. For this reason, your doctor may advise that you avoid alcohol consumption during Effexor XR treatment. If you have questions about the safety of Effexor XR and alcohol, talk with your doctor or pharmacist.

If you’d like to learn more about Effexor XR, talk with your doctor or pharmacist. They can help answer any questions you have about side effects from taking the drug.

Besides talking with your doctor, you can do some research on your own. These articles might help:

  • More information about Effexor XR. For details about other aspects of Effexor XR, refer to this article.
  • Cost. If you’d like to learn about venlafaxine (the generic version of Effexor XR) and cost, see this article.
  • Dosage. For information about the dosage of Effexor XR, view this article.
  • A look at your condition. For details about the conditions Effexor XR is prescribed to treat, see our hubs on depression, anxiety, and mental health.

Disclaimer: Medical News Today 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 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.