Desvenlafaxine ER (generic for Pristiq®)

Desvenlafaxine is the generic equivalent of Pristiq®. This drug only comes in the form of extended-release tablets.

By law, a generic drug must be the same as its brand name counterpart in terms of active ingredient, dosage, safety, effectiveness, strength, stability, and quality. A generic may, however, differ in its inactive ingredients (i.e. flavoring, fillers, and preservatives).

Desvenlafaxine ER (Pristiq®) does come with serious warnings. These include:

• Increased risk of suicidal thoughts or actions*

• Serotonin syndrome—a rare, but potentially life-threatening condition that occurs when there’s too much serotonin in the brain

• High blood pressure or changes in blood pressure—must be monitored periodically

• Increased risk of bleeding, bleeding problems

• Angle-closure glaucoma

• Manic episodes or hypomania in patients with bipolar disorder

• Risk of high cholesterol and triglyceride levels

• Withdrawal symptoms—abrupt discontinuation of treatment can cause nausea, anxiety, confusion, and headache

• Seizure

• Lung disease and pneumonia

If any of the above concern you, speak with your doctor or pharmacist about your perceived risk and other treatment options that exist.

*This warning is a boxed warning. A boxed warning is the most serious type of medication warning assigned by the FDA.

Desvenlafaxine is an SNRI (serotonin-norepinephrine reuptake inhibitor). It works by blocking the brain’s absorption of norepinephrine and serotonin, “feed good” chemicals in your brain. The end result? An increased level of norepinephrine and serotonin in your brain, which is thought to improve mood and pain.

Desvenlafaxine is FDA approved for the treatment of:

• Major depressive disorder (MDD) or depression

Desvenlafaxine may also be used off-label for:

• Hot flashes during menopause

• Generalized anxiety

• Social anxiety

• Panic attacks

The most common side effects of desvenlafaxine include:

• Nausea/vomiting

• Dizziness

• Trouble sleeping

• Tiredness

• Excessive sweating (hyperhidrosis)

• Constipation

• Decreased appetitie

• Anxiety

• Sexual dysfunction in males

• Decreased sex drive

• Dry mouth

Side effects may improve over time as your body adjusts to the medicine.

This list doesn’t represent all possible side effects (or serious side effects) of desvenlafaxine. If you’re experiencing any ongoing, bothersome side effect(s), tell your healthcare provider right away.

If you’d like to learn more, speak with your doctor or pharmacist. The Food and Drug Administration (FDA) also has a helpful medication guide for desvenlafaxine here.

Desvenlafaxine can interact with some prescription drugs and supplements. It’s always recommended to give both your doctor and pharmacy an updated list of everything you’re taking, so drug interactions can be identified.

Some medicines and supplements desvenlafaxine can interact with include:

• SSRIs (selective serotonin reuptake inhibitors): citalopram, sertraline, fluoxetine, paroxetine

• Monoamine oxidase inhibitors (MAOIs): selegiline, phenelzine, linezolid, methylene blue, tranylcypromine, isocarboxazid

• SNRIs (serotonin and norepinephrine reuptake inhibitors): venlafaxine (Effexor),, duloxetine, milnacipran

• Triptans: sumatriptan, eletriptan, naratriptan

• Arrhythmia medications: propafenone, flecainide

• Alcohol

• Buspirone

• NSAIDs (nonsteroidal anti-inflammatory drugs): aspirin, ibuprofen

• Warfarin

• Lithium

• Tramadol

• Cimetidine

• St. John’s Wort

• Ciprofloxacin

• Weight loss medications

• Amphetamines

This list doesn’t represent all the drugs that may not be safe to take with desvenlafaxine. If you’re unsure whether a certain drug or supplement can be taken with desvenlafaxine, seek medical advice from your doctor or pharmacist. The FDA also has a helpful medication guide for desvenlafaxine here.

If you accidentally miss your dose of desvenlafaxine, take the dose as soon as you remember. If it’s almost time for your next dose, skip the missed dose and take your next dose at the usual time. Don't take 2 doses at the same time or extra doses.

Desvenlafaxine may be taken with or without food.

During pregnancy: Limited data exists on the effects of desvenlafaxine-use during pregnancy. According to some data, newborns who were exposed to antipsychotic drugs during the 3rd trimester of pregnancy may be at risk for experiencing withdrawal symptoms following delivery.

While breastfeeding: Desvenlafaxine is excreted in breastmilk and there is a risk for serious adverse reactions in nursing infants.

It’s important to treat mental health-related conditions when pregnant or nursing, as untreated depression, anxiety, or other mental illnesses can harm both you and baby. Always let your provider know if you’re pregnant or breastfeeding, so you can discuss alternative treatment options.

It’s recommended to avoid or limit the use of alcohol when taking desvenlafaxine. Drinking alcohol can intensify the side effects of desvenlafaxine, including dizziness, mental impairment and sleepiness.