Pristiq is a treatment option for depression.

Pristiq is a prescription drug that’s used to treat major depressive disorder in adults.

The active ingredient in Pristiq is desvenlafaxine. An active ingredient is what makes a drug work. Pristiq comes as a tablet that you swallow. It’s usually taken long term.

For more information about Pristiq, including details about its uses, see this in-depth article.

Pristiq can cause mild to serious side effects. Continue reading to learn more.

Some people may experience side effects during Pristiq treatment. Some of the reported side effects of Pristiq are listed here.

The side effects explained section is where you can learn more about this side effect.

There are other possible side effects of Pristiq.

Mild side effects may occur with Pristiq. Mild side effects have been reported with Pristiq.

The side effects explained section is where you can learn more about this side effect.

These side effects should be temporary. Some may be easy to manage. If you have any symptoms that bother you, talk to your doctor or pharmacist. Unless your doctor recommends it, you should not stop taking Pristiq.

Pristiq may cause mild side effects other than the ones listed above. See the Pristiq prescribing information for details.

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

Pristiq can cause serious side effects, though these are usually rare. Serious side effects that have been reported with Pristiq are listed below. Some of these side effects were reported in studies of Pristiq. But others were reported after the drug became available on the market.

* Pristiq has a boxed warning for this side effect. This is the most serious warning from the Food and Drug Administration (FDA). To learn more, see the “Side effects explained” section below.
† To learn more about this side effect, see the “Side effects explained” section below.
‡ An allergic reaction is possible after taking Pristiq. But this side effect wasn’t reported in studies.

If you develop serious side effects while taking Pristiq, call your doctor. If the side effects seem life threatening or you think you have a medical emergency, immediately call the emergency number.

Get answers to questions about Pristiq.

Does Pristiq cause weight gain?

It’s possible. In studies of Pristiq, weight gain was not a reported side effect. But after Pristiq was made available on the market, some people who took it reported gaining weight.

It’s important to note that weight changes, including weight gain, can be a symptom of depression.

If you notice weight gain while taking Pristiq, talk to your doctor. They may have tips to help.

If I suddenly stop taking Pristiq, will I have withdrawal symptoms?

It is possible. Mild or serious withdrawal symptoms can be caused by stopping Pristiq. Mild symptoms of withdrawal include:

There are some serious symptoms of withdrawal.

“If you stop taking Pristiq suddenly, you’re more likely to have these side effects. If you want to stop taking Pristiq, you should talk to your doctor. They recommend taking a smaller dose of Pristiq instead of stopping it abruptly. It may take several months to stop taking Pristiq.”

Will my risk of side effects be higher with the 100-mg dose of Pristiq than with lower doses of the drug?

It’s possible. During studies of Pristiq, people took different doses of the drug. The side effects that were reported were the same for each dosage. But more people who took the 100-milligram (mg) dose reported certain side effects than those who took the 50-mg dose. Some of these side effects were:

  • The mouth is dry.
  • It is too sleepy.
  • “It’s difficult to sleep.”
  • certain Sexual side effects.
  • nausea

The side effects explained section is where you can learn more about this side effect.

Some of the side effects of Pristiq can be found here.

Risk of suicidal thoughts and actions

Pristiq carries a boxed warning about the risk of suicidal thoughts and actions in children, adolescents, and adults ages 24 years and younger. A boxed warning is the most serious warning from the Food and Drug Administration (FDA).

People under 25 years of age are at increased risk of suicidal thoughts and actions. The FDA has not approved the use of Pristiq in people under the age of 18.

There are symptoms of suicidal thoughts and actions.

What might help

Keep a record of how you feel. If you experience any of the symptoms listed above, you should immediately tell your doctor.

Let people know about the Pristiq side effect. They can help you watch out for the symptoms.

If you are under the age of 18 you may be monitored more closely by your doctor for suicidal thoughts and actions.

Suicide prevention

If you know someone who is at risk of self-injury, suicide or hurting another person.

  • Ask the tough question, “Are you considering suicide?”
  • Listen to the person.
  • To speak with a trained crisis counselor, call or text the number.
  • Stay with the person until help arrives.
  • Weapons, medications, or other potentially harmful objects should be removed.

A prevention hotline can help if you or someone you know is thinking about suicide. You can call the Suicide and Crisis Hotline at 988 if you need it. People who are hard of hearing can use their preferred relay service, which is 711 or 800-273-8255.

Click here for more local resources.

Sexual side effects

Antidepressants such as Pristiq may cause sexual side effects. In studies of the drug, males* reported:

In studies of the drug, females* reported:

* 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, see this article.

What might help

Sexual side effects may diminish on their own. Sometimes, a switch to a different drug may help. If you experience any sexual side effects while taking Pristiq, tell your doctor. They can suggest ways to make it easier to have sex.

Nausea

In studies, nausea was a common side effect of Pristiq. By itself, nausea may be considered a mild side effect. But it can be a symptom of withdrawal, which may occur if you stop taking Pristiq suddenly. (For more information, see the “FAQs about Pristiq’s side effects” section above.)

Nausea may also be a symptom of serotonin syndrome. This is a serious condition that can happen when too much serotonin builds up in the body.

Other symptoms of the syndrome include:

What might help

If you have nausea with Pristiq, the following tips may help.

  • Take your dose with some crackers.
  • Drinks and foods with ginger are good.
  • Ask your doctor about the drugs that can help you.

If you experience nausea that is severe or symptoms of a syndrome called Serotonin Syndrome, seek medical care.

Headache

Headache was a common side effect in short-term studies of Pristiq. This side effect was usually mild.

“If you suddenly stop Pristiq, this side effect may occur. The FAQs about Pristiq’s side effects are above.”

Headaches may be a symptom of a low blood level of sodium. This is a side effect of certain antidepressants such as Pristiq, and it can be a serious problem. Older adults (ages 65 years and older) and people who take diuretics may have a higher risk of this side effect. Symptoms to watch out for include:

What might help

Mild There is a throbbing head.s may lessen a few weeks after starting Pristiq. But if this side effect continues to bother you, talk with your doctor. They may recommend medications to treat your There is a throbbing head.s.

If your There is a throbbing head.s occur with the other symptoms of a low blood level of sodium listed above, seek immediate medical treatment.

Constipation

Constipation was a common, mild side effect in studies of Pristiq.

What might help

“After taking Pristiq for a few weeks, it’s usually all over. Mild exercise and drinking more water may help with this side effect.”

If you experience severe scurvy, talk to your doctor. They may suggest changes to your diet or medication to help you with this side effect.

Allergic reaction

Like most drugs, Pristiq can cause an allergic reaction in some people. But this side effect wasn’t reported in studies.

Mild to serious symptoms can be present.

  • There is a skin rash.
  • It is itchy.
  • flushing (temporary warmth, redness, or deepening of skin color)
  • “It’s usually under your skin, but it can be anywhere.”
  • It can be hard to breathe if you have swelling of your mouth, tongue, or throat.

What might help

If you have a mild rash, call your doctor. They may suggest ways to manage your symptoms. Examples include:

  • an antihistamine you take by mouth, such as Benadryl (diphenhydramine)
  • You apply a product to your skin.

If your doctor confirms you have an allergic reaction to Pristiq, they will decide if you should continue taking it.

If you have a severe allergic reaction, you should call the emergency number. These symptoms could be life threatening and need immediate medical care.

If your doctor confirms you have had a serious allergic reaction to Pristiq, they may have you switch to a different treatment.

Keeping track of side effects

Take notes on any side effects you are having during your Pristiq treatment. You can share this information with your doctor. This is helpful when you are starting to use a combination of treatments.

Side effect notes can include things.

  • When you had the side effect, what dose of the drug was taking?
  • How soon did you experience the side effect?
  • What are your symptoms?
  • How did it affect your daily activities?
  • What other drugs were you taking?
  • Other information is important to you.

Sharing your notes with your doctor will help them learn more about how Pristiq affects you. If needed, they can use this information to adjust your treatment plan.

Pristiq has several warnings.

Boxed warning: Risk of suicidal thoughts and actions

Pristiq has a boxed warning for the risk of suicidal thoughts and actions in children, adolescents, and adults ages 24 years and younger. A boxed warning is the most serious warning from the Food and Drug Administration (FDA).

To learn more, see the “Side effects explained” section above.

Other warnings

Drug-condition interactions may be caused by Pristiq. If you have certain medical conditions, Pristiq may not be right for you. Other factors may affect whether Pristiq is a good option.

Before starting Pristiq, you should talk to your doctor about your health history. The list has factors to consider.

High blood pressure. Pristiq can cause your blood pressure to increase.If you have high blood pressure, your doctor may prescribe medication to treat it before you start taking Pristiq. Then they’ll monitor your blood pressure to make sure it’s well-managed. If your blood pressure remains high, your doctor may adjust your dosage of Pristiq or recommend a different antidepressant.

Heart disease. If you have heart disease, Pristiq may make it worse. Pristiq can increase your blood pressure, which may worsen heart disease. If you have a history of heart disease or high blood pressure, tell your doctor before starting Pristiq treatment.

Stroke or ministroke. Pristiq can increase your blood pressure, so it may increase your risk of stroke if you’ve had one before. If you’ve had a stroke or if you’ve had any problems with high blood pressure, let your doctor know. This will help them determine whether it’s safe for you to take Pristiq.

Bleeding problems. Medications like Pristiq may increase your risk of bleeding. If you take medications that increase bleeding, your risk may be greater. Before you take Pristiq, make sure your doctor knows all of the medications you take.

Angle-closure glauA A coma… Pristiq may cause dilation of the pupils in the eye. This can cause an episode of glauA A coma.. in certain people. Because of this, doctors will likely not prescribe Pristiq to anyone with this kind of glauA A coma… If you have a history of glauA A coma.. or if you take any eye drops for glauA A coma.., tell your doctor. They’ll discuss with you treatment options that are safe for you to take.

Mania, hypomania, or bipolar disorder. Pristiq may not be the right medication for people who have had mania, hypomania, or bipolar disorder. It also may not be safe for people who have a family history of these mental health conditions. If you have bipolar disorder, Pristiq can increase your risk of a manic episode. Before you start Pristiq treatment, tell your doctor about any mental health conditions you or close family members have had.

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

Seizures or epilepsy. Pristiq was not studied in people with a history of Seizures. or epilepsy. If you’ve ever had a There was a There was a There was a seizure… or have epilepsy, tell your doctor. They’ll let you know if Pristiq is safe for you to take.

Low sodium level. Pristiq can lower the blood level of sodium, which can become a serious problem. Older adults (ages 65 years and older) or people who take diuretics may have a higher risk of this side effect. If you are an older adult or take a diuretic, or have had problems with a low sodium level in the past, your doctor will let you know whether it’s safe to take Pristiq.

Liver problems. If you have liver problems, your body may have trouble getting rid of Pristiq. Before you start treatment, tell your doctor about any liver problems you have or have had. They may prescribe a lower dosage of Pristiq.

Kidney problems. If you have kidney problems, your body may have trouble getting rid of Pristiq. Before you start treatment, tell your doctor about any kidney problems you have or have had. They may recommend that you take a lower dosage of Pristiq.

High cholesterol or triglycerides. Pristiq may increase cholesterol or triglycerides in certain people. If you’ve had high cholesterol or triglycerides or take medication to treat these conditions, tell your doctor. They may recommend more frequent blood tests to check levels of these substances while you’re taking Pristiq.

Alcohol and Pristiq

You should not take Pristiq with alcohol. Alcohol may increase your risk of side effects and may make depression worse.

If you drink alcohol, tell your doctor. They can suggest ways to stop drinking or recommend a different medication.

Pregnancy and breastfeeding while taking Pristiq

If you are pregnant or planning to become pregnant, you should talk to your doctor. They can help you decide if Pristiq is the best choice for you.

Certain antidepressants can increase the risk of preeclampsia or bleeding complications during pregnancy. Taking Pristiq in the third trimester of pregnancy may cause withdrawal symptoms in your newborn.

If you become pregnant during treatment with Pristiq, ask your doctor about registering with the National Pregnancy Registry for Antidepressants. This registry gathers data from people who’ve taken Pristiq while pregnant. This data can help determine the safety of taking antidepressants such as Pristiq during pregnancy.

Breast milk may contain small amounts of Pristiq. It is not known if Pristiq is safe to take during breastfeeding. If you are planning to breastfeeding or are about to, talk to your doctor about how to feed your child safely during treatment with Pristiq.

Pristiq may help treat your depression symptoms. Some people have mild side effects from the drug, such as nausea and constipation. More serious side effects from Pristiq aren’t common.

If you have questions about Pristiq, you can talk to your doctor or pharmacist. There are a few questions to ask about treatment.

  • Is my risk of sexual side effects higher when I start treatment?
  • Does my risk of nausea and vomiting depend on what dose I take?
  • Does Pristiq have more side effects than other drugs?

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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 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.