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.
You should not use this medicine if you are allergic to desvenlafaxine or venlafaxine (Effexor), or if you are being treated with methylene blue injection.
Do not use desvenlafaxine if you are taking an MAO inhibitor. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, phenelzine, rasagiline, selegiline, and tranylcypromine. 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.
To make sure desvenlafaxine is safe for you, tell your doctor if you have:
- bipolar disorder (manic depression);
- liver or kidney disease;
- heart disease, high blood pressure, high cholesterol, or a history of stroke;
- seizures or epilepsy;
- a history of stroke;
- a bleeding or blood clotting disorder;
- low levels of sodium in your blood; or
- if you are switching to desvenlafaxine from another antidepressant.
Some young people have thoughts about suicide when first taking an antidepressant. Your doctor will need to check your progress at regular visits while you are using desvenlafaxine. Your family or other caregivers should also be alert to changes in your mood or symptoms.
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. Tell 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.
Get emergency medical help if you have any of these signs of an allergic reaction: skin rash or hives; difficulty breathing; swelling of your face, lips, tongue, or 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.
Call your doctor at once if you have:
- seizure (convulsions);
- agitation, hallucinations, fever, fast heart rate, overactive reflexes, nausea, vomiting, diarrhea, loss of coordination;
- 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;
- very stiff (rigid) muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, feeling like you might pass out;
- headache, slurred speech, severe weakness, muscle cramps, feeling unsteady, fainting, shallow breathing (breathing may stop);
- severe skin reaction — fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain, followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.
Common side effects may include:
- dizziness, drowsiness, anxiety;
- increased sweating;
- mild nausea, loss of appetite, constipation;
- sleep problems (insomnia); or
- decreased sex drive, impotence, or difficulty having an orgasm.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.