Pristiq (desvenlafaxine) is a brand-name prescription medication. The Food and Drug Administration (FDA) has approved it to treat major depressive disorder in adults. This disorder is frequently referred to as depression.

Pristiq comes as an extended-release oral tablet. It contains the active drug desvenlafaxine. Pristiq belongs to a class of drugs called serotonin-norepinephrine reuptake inhibitors (SNRIs).

Pristiq is available as a brand-name medication. It also comes in a generic version called desvenlafaxine. Generic drugs are usually less expensive than their brand-name form.

For information about the dosage of Pristiq, including its strengths and how to take the drug, keep reading. For a comprehensive look at Pristiq, see this article.

This article describes typical dosages for Pristiq provided by the drug’s manufacturer. When taking Pristiq, always follow the dosage prescribed by your doctor.

Pristiq is approved to treat major depressive disorder in adults. This disorder is frequently referred to as depression.

Pristiq form

Pristiq comes as an extended-release oral tablet. With this type of tablet, the drug is released into your body slowly.

Pristiq strengths (25 mg, 50 mg, 100 mg)

Pristiq is available in three strengths: 25 milligrams (mg), 50 mg, and 100 mg.

Typical dosages

Typically, your doctor will start you on a low dosage. Then, they’ll adjust it over time to reach the amount that’s right for you. Your doctor will ultimately prescribe the smallest dosage that provides the desired effect.

The following information describes dosages that are commonly used or recommended. However, be sure to take the dosage your doctor prescribes for you. Your doctor will determine the best dosage to fit your needs.

Dosage for depression

The typical Pristiq starting dose is 50 mg. This is taken once per day.

The lowest dose of Pristiq is 25 mg, while the maximum dose (highest dose) of Pristiq is 400 mg. This is known as the dose range. The lowest or maximum dose is typically taken once per day.

It’s important to note that Pristiq dosages higher than 50 mg per day have not been shown to be more effective than lower doses. Higher doses of the drug are also more likely to cause side effects. (For details about Pristiq’s side effects, see this article.)

Your doctor will monitor how well Pristiq is treating your condition. They may increase the dosage if the drug is not working well enough for your symptoms.

Ultimately, your doctor’s goal is for you to have a therapeutic dose of Pristiq. A therapeutic dose is the amount that best treats your condition with minimal side effects.

Children’s dosage

The Food and Drug Administration (FDA) has not approved Pristiq for use in children.* If your child has depression, talk with their doctor about treatment options.

* Pristiq has a boxed warning about the risk of suicidal thoughts and behavior in some children and young adults. This is a serious warning from the Food and Drug Administration (FDA). A boxed warning alerts doctors and patients about drug effects that may be dangerous.

Long-term treatment

Pristiq is meant to be taken as a long-term treatment. If you and your doctor determine that Pristiq is safe and effective for you, you’ll likely take it long term.

Below are answers to some frequently asked questions about Pristiq.

What are the average, lowest, and maximum doses of Pristiq?

The typical (average) Pristiq dose is 50 milligrams (mg). The lowest dose is 25 mg, and the maximum dose is 400 mg.

Keep in mind that Pristiq dosages higher than 50 mg per day haven’t been shown to be more effective than lower dosages. Higher doses of the drug are also more likely to cause side effects. (To learn more about side effects of Pristiq, see this article.)

Your doctor can help determine what Pristiq dose is right for you.

Is there a Pristiq dosage for anxiety?

Pristiq is not approved to treat anxiety or social anxiety disorder. However, doctors may prescribe Pristiq off-label. Off-label drug use is when a drug the Food and Drug Administration (FDA) approved is prescribed for a purpose other than what it’s approved for.

It’s important to note that Pristiq isn’t typically prescribed to treat anxiety disorders. This is because more studies are necessary to show whether the drug is effective for this purpose.

If you’re interested in taking Pristiq to treat anxiety, talk with your doctor. They can recommend treatment options that are safe and effective to treat your anxiety.

When would my doctor prescribe a 150-mg or 200-mg dose of Pristiq?

If you have symptoms of depression with a lower Pristiq dose, your doctor may increase it to 150 mg or 200 mg. It’s possible they could prescribe a maximum dose of up to 400 mg.

Higher doses of Pristiq are more likely to cause more side effects. So, your doctor will prescribe the lowest dose that helps your depression. (To learn more about side effects of Pristiq, see this article.)

For additional information about your Pristiq treatment, talk with your doctor.

What side effects can I expect with a 100-mg Pristiq dose?

The manufacturer of Pristiq hasn’t reported specific side effects that occur with a 100-mg dose of the drug. Some side effects that may occur while taking any dose of Pristiq can include:

For more details on these side effects and additional side effects that are possible while taking Pristiq, see this article. You can also talk with your doctor and pharmacist.

If you miss a dose of Pristiq, take it as soon as you remember. If it’s almost time for your next dose, skip the missed dose and take your next dose at your usual time. Your doctor or pharmacist can help determine whether or not to take or skip a missed dose.

Keep in mind that you should not take two doses to make up for a missed dose. Taking multiple doses can increase your risk of certain side effects. (To learn more about side effects of Pristiq, see this article.)

To help make sure that you don’t miss a dose, try using a medication reminder. This can include setting an alarm or using a timer. You could also download a reminder app on your phone.

The Pristiq dosage your doctor prescribes will depend on several factors. These include:

  • the severity of the condition you’re taking Pristiq to treat
  • your age

Other medical conditions you may have can also affect your Pristiq dosage.

Dosage adjustments

If you have certain medical conditions, your doctor may prescribe a lower dose of Pristiq. These include kidney or liver problems, such as kidney failure or liver failure.

Be sure to let your doctor know of any kidney, liver, or other medical conditions you have before starting Pristiq treatment.

Pristiq comes as an oral tablet that you swallow. You should not crush, split, or chew Pristiq tablets. If you have trouble swallowing tablets, see this article for tips on how to take this form of medication. You can also talk with your doctor or pharmacist.

You can take Pristiq with or without food. It’s best to take the drug around the same time each day. This helps keep a steady level of the drug in your body so Pristiq can work effectively.


If you’re having trouble reading your prescription label, talk with your doctor or pharmacist. Some pharmacies offer labels with large print, braille, or a code you scan with a smartphone to convert text to speech. If your local pharmacy doesn’t have these options, your doctor or pharmacist might be able to recommend a pharmacy that does.

If you’re having trouble opening medication bottles, ask your pharmacist about putting Pristiq in an easy-open container. They also may recommend tools that can make it easier to open bottles.

If you take more Pristiq than your doctor prescribes, you may develop serious side effects.

It’s important that you do not take more Pristiq than your doctor advises.

Symptoms of an overdose

Overdose symptoms of Pristiq can include:

An overdose of Pristiq may, in some cases, be fatal. Your doctor can tell you more.

If you take more than the recommended amount of Pristiq

Call your doctor right away if you believe you’ve taken too much Pristiq. Another option is to call the American Association of Poison Control Centers at 800-222-1222 or use its online tool. If you have severe symptoms, immediately call 911 or your local emergency number, or go to the nearest emergency room.

Stopping Pristiq treatment too quickly can cause withdrawal symptoms that may last days to weeks. (Withdrawal symptoms are side effects that can occur when you stop taking a drug that your body has become dependent on.) Because of this, you should not stop taking this drug without first consulting your doctor.

Some symptoms of withdrawal include:

  • nausea
  • sweating
  • diarrhea
  • dizziness
  • headache
  • anxiety
  • irritability or agitation (feeling nervous, annoyed, or restless)
  • confusion

For more details, including additional withdrawal symptoms that may occur with Pristiq, see this article.

If you and your doctor determine that you should stop taking Pristiq, they’ll decrease your dose slowly. Doing so can help you avoid withdrawal symptoms. It’s important you do not suddenly stop taking your medication or change your dose unless your doctor has instructed you to do so.

The dosages in this article are typical dosages provided by the drug’s manufacturer. If your doctor recommends Pristiq for you, they’ll prescribe the dosage that’s right for you. Always follow the dosage that your doctor prescribes.

As with any drug, never change your dosage of Pristiq without your doctor’s recommendation. If you have questions about the dosage of Pristiq that’s best for you, talk with your doctor.

Besides learning about dosage, you may want other information about Pristiq. These additional articles might be helpful:

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.