Drug Database - Desvenlafaxine

Generic Name: desvenlafaxine (des-VEN-la-FAX-een)

Brand Names: Pristiq®

Classification: Selective Serotonin and Norepinephrine Reuptake Inhibitors (SNRIs)

Desvenlafaxine is an antidepressant in a group of drugs called selective serotonin and norepinephrine reuptake inhibitors (SNRIs). Desvenlafaxine affects chemicals in the brain that may become unbalanced and cause depression. Desvenlafaxine is used to treat major depressive disorder along with other off-label uses.

Important Facts

You should not take this medication if you are allergic to desvenlafaxine or venlafaxine (Effexor), or if you are also using a monoamine oxidase inhibitor (MAOI) such as:

• furazolidone (Furoxone)
• isocarboxazid (Marplan)
• phenelzine (Nardil)
• rasagiline (Azilect)
• selegiline (Eldepryl, Emsam)
• tranylcypromine (Parnate)

You must wait at least 14 days after stopping an MAOI before you can take desvenlafaxine. After you stop taking desvenlafaxine, you must wait at least 7 days before you start taking an MAOI.

You should not take desvenlafaxine together with venlafaxine (Effexor).

You may have thoughts about suicide when you first start taking an antidepressant, especially if you are younger than 24 years old. Your doctor will need to check you at regular visits for at least the first 12 weeks of treatment.

Call your doctor at once if you have any new or worsening symptoms such as:

• mood or behavior changes
• anxiety
• panic attacks
• trouble sleeping
• or if you feel:
• impulsive
• irritable
• agitated
• hostile
• aggressive
• restless
• hyperactive (mentally or physically)
• more depressed
• or have thoughts about suicide or hurting yourself

It may take several weeks before your symptoms improve. Keep using the medication as directed and tell your doctor if your symptoms do not improve after a few weeks of treatment. Do not stop using desvenlafaxine suddenly, or you could have unpleasant symptoms. Ask your doctor how to avoid these symptoms when you stop using desvenlafaxine.

How To Take Desvenlafaxine

Take exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label.

Take this medicine with a full glass of water. Desvenlafaxine can be taken with or without food. Try to take the medicine at the same time each day. Do not crush, chew, break, or dissolve the extended-release tablet. Swallow the pill whole. Breaking or dissolving the pill may cause too much of the drug to be released into the body at one time.

The desvenlafaxine tablet is made with a shell that is not absorbed or melted in the body. Part of the tablet shell may appear in your stool. This is a normal side effect of desvenlafaxine and will not make the medication less effective.

It may take several weeks before your symptoms improve. Keep using the medication as directed and tell your doctor if your symptoms do not improve after a few weeks of treatment. Do not stop using desvenlafaxine suddenly, or you could have unpleasant symptoms. Ask your doctor how to avoid these symptoms when you stop using desvenlafaxine.

Your blood pressure will need to be checked often. Visit your doctor regularly.

If You Forget A Dose

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

In Case of Overdose

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center ( http://www.aapcc.org/findyour.htm), or emergency room IMMEDIATELY.

Symptoms may include:

• vomiting
• agitation
• fast heart rate
• numbness or tingly

You should not take this medication if you are allergic to desvenlafaxine or venlafaxine (Effexor), or if you are also using a monoamine oxidase inhibitor (MAOI) such as:

• furazolidone (Furoxone)
• isocarboxazid (Marplan)
• phenelzine (Nardil)
• rasagiline (Azilect)
• selegiline (Eldepryl, Emsam)
• tranylcypromine (Parnate)

You must wait at least 14 days after stopping an MAOI before you can take desvenlafaxine. After you stop taking desvenlafaxine, you must wait at least 7 days before you start taking an MAOI.

Do not take desvenlafaxine together with venlafaxine (Effexor).

If you have any of these other conditions, you may need a desvenlafaxine dose adjustment or special tests:

• bipolar disorder (manic depression)
• liver disease
• kidney disease
• heart disease, high blood pressure, high cholesterol
• a history of stroke
• glaucoma
• seizures or epilepsy
• a bleeding or blood clotting disorder
• if you are switching to desvenlafaxine from another antidepressant

You may have thoughts about suicide when you first start taking an antidepressant, especially if you are younger than 24 years old. Tell your doctor if you have worsening symptoms of depression or suicidal thoughts during the first several weeks of treatment, or whenever your dose is changed.

Your family or other caregivers should also be alert to changes in your mood or symptoms. Your doctor will need to check you at regular visits for at least the first 12 weeks of treatment.

FDA pregnancy category C. Desvenlafaxine may cause problems in a newborn baby if the mother takes the medication late in pregnancy (during the third trimester). Tell your doctor if you are pregnant or plan to become pregnant during treatment. Desvenlafaxine can pass into breast milk and may harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby. Do not give this medication to anyone under 18 years old without the advice of a doctor.

Side Effects

Get emergency medical help if you have any of these signs of an allergic reaction:

• hivess
• difficulty breathing
• swelling of your face
• lips
• tongue
• throat

Report any new or worsening symptoms to your doctor, such as: mood or behavior changes, anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), more depressed, or have thoughts about suicide or hurting yourself.

Seek medical attention right away if any of these SEVERE side effects occur:

• seizure (convulsions)


• very stiff (rigid) muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, feeling like you might pass out


• agitation, hallucinations, fever, fast heart rate, overactive reflexes, nausea, vomiting, diarrhea, loss of coordination


• headache, trouble concentrating, memory problems, weakness, feeling unsteady, confusion, hallucinations, fainting, shallow breathing or breathing that stops


• blurred vision, eye pain, or seeing halos around lights


• cough, chest tightness, trouble breathing


• easy bruising or bleeding (nosebleeds, bleeding gums), blood in your urine or stools, coughing up blood.

Check with your doctor if any of these most COMMON side effects persist or become bothersome:

• dizziness, drowsiness, tired feeling
• dry mouth, loss of appetite
• constipation
• sleep problems (insomnia)
• mild headache
• decreased sex drive, impotence, or difficulty having an orgasm

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.

Before using desvenlafaxine, tell your doctor if you regularly use other medicines that make you sleepy (such as cold or allergy medicine, sedatives, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for seizures or anxiety). They can add to sleepiness caused by desvenlafaxine. Tell your doctor about all other medications you use, especially:

• a blood thinner such as warfarin (Coumadin)


• linezolid (Zyvox)


• lithium (Eskalith, Lithobid)


• midazolam (Versed)


• sibutramine (Meridia)


• St. John's wort


• tramadol (Ultram, Ultracet)


• tryptophan (sometimes called L-tryptophan)


• an antibiotic such as:
• clarithromycin (Biaxin)
• erythromycin (E.E.S., EryPed, Ery-Tab, Erythrocin)
• telithromycin (Ketek)
• and others


• antifungal medication such as:
• clotrimazole (Mycelex Troche)
• itraconazole (Sporanox)
• ketoconazole (Extina, Ketozole, Nizoral, Xolegal)
• or voriconazole (Vfend)


• aspirin or other NSAIDs (non-steroidal anti-inflammatory drugs) such as:
• ibuprofen (Motrin, Advil)
• naproxen (Aleve, Naprosyn)
• diclofenac (Cataflam, Voltaren)
• etodolac (Lodine)
• indomethacin (Indocin)
• and others


• heart or blood pressure medication such as:
• diltiazem (Cartia, Cardizem)
• nifedipine (Nifedical, Procardia)
• verapamil (Calan, Covera, Isoptin, Verelan)
• and others


• HIV/AIDS medicine such as:
• fosamprenavir (Lexiva)
• indinavir (Crixivan)
• ritonavir (Norvir)
• and others


• migraine headache medication such as:
• sumatriptan (Imitrex, Treximet)
• almotriptan (Axert)
• frovatriptan (Frova)
• naratriptan (Amerge)
• rizatriptan (Maxalt)
• zolmitriptan (Zomig)


• any other antidepressant such as:
• amitriptyline (Elavil)
• citalopram (Celexa)
• doxepin (Sinequan)
• duloxetine (Cymbalta)
• fluoxetine (Prozac)
• nefazodone
• nortriptyline (Pamelor)
• paroxetine (Paxil)
• sertraline (Zoloft)
• and others.