Desvenlafaxine

Conditions Treated

Desvenlafaxine is used to treat depression. Desvenlafaxine is in a class of medications called selective serotonin and norepinephrine reuptake inhibitors (SNRIs). It works by increasing the amounts of serotonin and norepinephrine, natural substances in the brain that help maintain mental balance.

Possible Side Effects

What Side Effects Can This Cause?

Desvenlafaxine may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• constipation
• loss of appetite
• dry mouth
• dizziness
• extreme tiredness
• unusual dreams
• yawning
• sweating
• uncontrollable shaking of a part of the body
• pain, burning, numbness, or tingling in part of the body
• enlarged pupils (black circles in the centers of the eyes)
• blurred vision
• changes in sexual desire or ability
• difficulty urinating

Some side effects can be serious. If you experience any of these symptoms or those listed in the IMPORTANT WARNING section, call your doctor immediately:

• rash
• hives
• swelling
• difficulty breathing
• fast heartbeat
• cough
• chest pain
• fever
• coma (loss of consciousness for a period of time)
• seizures
• hallucinations (seeing things or hearing voices that do not exist)
• fever, sweating, confusion, fast or irregular heartbeat, and severe muscle stiffness
• unusual bleeding or bruising
• nosebleeds
• small red or purple dots on the skin
• nausea
• vomiting
• diarrhea
• headache
• difficulty concentrating
• memory problems
• confusion
• weakness
• problems with coordination
• increased falls
• fainting

Desvenlafaxine may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online [at http://www.fda.gov/Safety/MedWatch] or by phone [1-800-332-1088].

Usage Instructions

How Should This Medication Be Used

Desvenlafaxine comes as an extended-release (long-acting) tablet to take by mouth. It is usually taken once a day with or without food. Take desvenlafaxine at around the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take desvenlafaxine exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor. Swallow the tablets whole with plenty of water; do not split, chew, crush, or dissolve them. Desvenlafaxine controls depression, but does not cure it. It may take several weeks before you feel the full benefit of desvenlafaxine. Continue to take desvenlafaxine even if you feel well. Do not stop taking desvenlafaxine without talking to your doctor. Your doctor will probably decrease your dose gradually. If you suddenly stop taking desvenlafaxine, you may experience withdrawal symptoms such as dizziness, nausea, headache, irritability, difficulty falling asleep or staying asleep, diarrhea, anxiety, extreme tiredness, unusual dreams, or sweating. Tell your doctor if you experience any of these symptoms while you are decreasing your dose of desvenlafaxine or soon after you stop taking desvenlafaxine.

What Dietary Instructions Should I Follow

Unless your doctor tells you otherwise, continue your normal diet.

Are There Any Special Instructions

Before taking desvenlafaxine, tell your doctor and pharmacist if you are allergic to desvenlafaxine, venlafaxine (Effexor), or any other medications. tell your doctor if you are taking a monoamine oxidase (MAO) inhibitor, such as isocarboxazid (Marplan), linezolid (Zyvox), phenelzine (Nardil), selegiline (Eldepryl, Emsam, Zelapar), and tranylcypromine (Parnate), or if you have stopped taking one of these medications within the past 14 days. Your doctor will probably tell you that you should not take desvenlafaxine. If you stop taking desvenlafaxine, your doctor will tell you that you should wait at least 7 days before you start to take an MAO inhibitor. you should know that desvenlafaxine is very similar to another SNRI, venlafaxine (Effexor). You should not take these medications together. tell your doctor and pharmacist what other prescription and nonprescription medications or vitamins you are taking or plan to take. Be sure to mention any of the following: anticoagulants ('blood thinners') such as warfarin (Coumadin); certain antifungals such as itraconazole (Sporanox) and ketoconazole (Nizoral); amiodarone (Cordarone, Pacerone); aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Motrin) and naproxen (Aleve, Naprosyn); clarithromycin (Biaxin); diuretics ('water pills'); lithium (Eskalith, Lithobid); medications for anxiety, mental illness, or seizures; certain medications for human immunodeficiency virus (HIV) such as indinavir (Crixivan), nelfinavir (Viracept), and ritonavir (Norvir); medications for migraine such as almotriptan (Axert), eletriptan (Relpax), frovatriptan (Frova), naratriptan (Amerge), rizatriptan (Maxalt), sumatriptan (Imitrex), and zolmitriptan (Zomig); midazolam; nefazodone; sedatives; selective serotonin reuptake inhibitors (SSRIs) such as citalopram (Celexa), escitalopram (Lexapro), fluoxetine (Prozac, Sarafem), fluvoxamine (Luvox), paroxetine (Paxil), and sertraline (Zoloft); other SNRIs such as duloxetine (Cymbalta); sibutramine (Meridia); sleeping pills; tramadol (Ultram); tranquilizers; and tricyclic antidepressants such as amitriptyline, amoxapine (Asendin), clomipramine (Anafranil), desipramine (Norpramin), doxepin (Sinequan), imipramine (Tofranil), nortriptyline (Aventyl, Pamelor), protriptyline (Vivactil), and trimipramine (Surmontil). Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Many other medications may also interact with desvenlafaxine, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list. tell your doctor what herbal products and nutritional supplements you are taking, especially St. John's wort and tryptophan. tell your doctor if you use or have ever used street drugs or have ever overused prescription medications. Also tell your doctor if you have recently had a heart attack and if you have or have ever had: bleeding problems; a stroke; high blood pressure; high cholesterol or triglycerides (fats in the blood); glaucoma (an eye disease); high pressure in the eyes (a condition that can lead to glaucoma); seizures; low sodium levels in the blood; or heart, kidney, or liver disease. if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking desvenlafaxine. you should know that desvenlafaxine may make you drowsy. Do not drive a car or operate machinery until you know how this medication affects you. ask your doctor about the safe use of alcoholic beverages while you are taking desvenlafaxine. Alcohol can make the side effects from desvenlafaxine worse.