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Drug


Effexor
venlafaxine
 



Generic Name:venlafaxine (oral)
Pronounced:ven la FAK seen
Brand Names:Effexor, Effexor XR

What is the most important information I should know about venlafaxine?

While you are taking venlafaxine you may need to be monitored for worsening symptoms of depression and/or suicidal thoughts at the start of therapy or when doses are changed. This concern about the increased risk of suicidal thoughts or behaviors may be greater if you are 18 years of age or younger and are taking venlafaxine. In patients younger than 18 years, the period of risk may extend beyond start of therapy or when doses are changed. Your doctor may want you to monitor for the following symptoms: anxiety, panic attacks, difficulty sleeping, irritability, hostility, impulsivity, severe restlessness, and mania (mental and/or physical hyperactivity). These symptoms may be associated with the development of worsening symptoms of depression and/or suicidal thoughts or actions. Contact your healthcare provider if you develop any new or worsening mental health symptoms during treatment with venlafaxine. Do not stop taking venlafaxine.
Do not take venlafaxine if you are currently taking or have taken a monoamine oxidase inhibitor (MAOI) such as isocarboxazid (Marplan), phenelzine (Nardil), or tranylcypromine (Parnate) in the last 14 days.
Use caution when driving, operating machinery, or performing other hazardous activities. Venlafaxine may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities.
Use alcohol cautiously. Alcohol may increase drowsiness, dizziness, and confusion
Do not stop taking venlafaxine without first talking to your doctor. Your doctor may need to gradually reduce the dose before stopping the medication completely. Stopping the medication suddenly may cause unpleasant side effects to occur.

What is venlafaxine?
Venlafaxine is an antidepressant medication. It affects chemicals in the brain that may become unbalanced and cause depression or anxiety.
Venlafaxine is used to relieve symptoms of depression, generalized anxiety disorder, and social anxiety disorder (social phobia).
Venlafaxine may also be used for purposes other than those listed in this medication guide.

What should I discuss with my healthcare provider before taking venlafaxine?
While you are taking venlafaxine you may need to be monitored for worsening symptoms of depression and/or suicidal thoughts at the start of therapy or when doses are changed. This concern about the increased risk of suicidal thoughts or behaviors may be greater if you are 18 years of age or younger and are taking venlafaxine. In patients younger than 18 years, the period of risk may extend beyond start of therapy or when doses are changed. Your doctor may want you to monitor for the following symptoms: anxiety, panic attacks, difficulty sleeping, irritability, hostility, impulsivity, severe restlessness, and mania (mental and/or physical hyperactivity). These symptoms may be associated with the development of worsening symptoms of depression and/or suicidal thoughts or actions. Contact your healthcare provider if you develop any new or worsening mental health symptoms during treatment with venlafaxine. Do not stop taking venlafaxine.
Do not take venlafaxine if you are currently taking or have taken a monoamine oxidase inhibitor (MAOI) such as isocarboxazid (Marplan), phenelzine (Nardil), or tranylcypromine (Parnate) in the last 14 days.
Before taking this medication, tell your doctor if you have
  • liver disease;
  • kidney disease;
  • heart disease or high blood pressure;
  • seizures or epilepsy;
  • a history of mania or bipolar disorder;
  • increased pressure in the eye(s) or narrow-angle glaucoma;
  • bleeding or blood clotting problems; or
  • increased level of cholesterol in the blood.
You may not be able to take venlafaxine, or you may require a dosage adjustment or special monitoring during treatment if you have any of the conditions listed above.
Venlafaxine is in the FDA pregnancy category C. Babies exposed to venlafaxine and/or other drugs of the same class during the third trimester of pregnancy may develop medical complications. Discuss the risks with your doctor. Do not take this medication without first talking to your doctor if you are pregnant or could become pregnant during treatment.
Venlafaxine passes into breast milk and may affect a nursing baby. Do not take venlafaxine without first talking to your doctor if you are breast-feeding a baby.

How should I take venlafaxine?

Take venlafaxine exactly as directed by your doctor. If you do not understand these directions, ask your pharmacist, nurse, or doctor to explain the instructions to you.
Take each dose with a full glass of water.
Take venlafaxine with food or milk to lessen stomach upset.
Venlafaxine should be taken at the same time every day.
Each Effexor XR capsule should be swallowed whole with fluid and not divided, crushed, chewed, or placed in water.
If swallowing of the Effexor XR capsules is difficult, a capsule may be carefully opened and the entire contents sprinkled onto a spoonful of applesauce. This drug/food mixture should be swallowed immediately without chewing and followed with a glass of water.
It is important to take venlafaxine regularly to get the most benefit.
Do not stop taking venlafaxine without first talking to your doctor. Your doctor may need to gradually reduce the dose before stopping the medication completely. Stopping the medication suddenly may cause unpleasant side effects to occur.
Your doctor may want you to have blood tests or other medical evaluations during treatment with venlafaxine to monitor progress and side effects.
Store venlafaxine at room temperature away from moisture and heat.

What happens if I miss a dose?
Take the missed dose as soon as you remember. However, if it is almost time for the next dose, skip the missed dose and take only the next one as directed. Do not take a double dose of this medication.

What happens if I overdose?
Seek emergency medical attention if an overdose is suspected.
Symptoms of a venlafaxine overdose may include dizziness, drowsiness, numbness, nausea, irregular heartbeats, seizures, and unconsciousness.

What should I avoid while taking venlafaxine?
Use caution when driving, operating machinery, or performing other hazardous activities. Venlafaxine may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities.
Avoid the use of alcohol. Alcohol may increase drowsiness, dizziness, and confusion while taking venlafaxine.

What are the possible side effects of venlafaxine?

If you experience any of the following serious side effects, stop taking venlafaxine and contact your doctor immediately or seek emergency medical treatment:
  • an allergic reaction (difficulty breathing; closing of the throat; swelling of the lips, tongue, or face; or hives);
  • seizures; or
  • an irregular heartbeat or severely high blood pressure (blurred vision, headache).
Other, less serious side effects may be more likely to occur. Continue to take venlafaxine and talk to your doctor if you experience
  • nausea, vomiting, upset stomach, abdominal pain, or loss of appetite or weight;
  • dry mouth;
  • drowsiness or dizziness;
  • mild tremor, anxiety, or agitation;
  • insomnia;
  • abnormal dreams;
  • sexual problems such as impotence, abnormal ejaculation, difficulty reaching orgasm, or decreased libido;
  • sweating;
  • yawning; or
  • increase in blood cholesterol levels (detected by blood tests);
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.

What other drugs will affect venlafaxine?
Do not take venlafaxine if you are currently taking or have taken a monoamine oxidase inhibitor (MAOI) such as isocarboxazid (Marplan), phenelzine (Nardil), or tranylcypromine (Parnate) in the last 14 days.
Venlafaxine may increase the effects of other drugs that cause drowsiness, including other antidepressants, anxiety medicines, antipsychotics, alcohol, antihistamines, sedatives (used to treat insomnia), pain relievers, and muscle relaxants. Tell your doctor about all medicines that you are taking, and do not take any other medicine without first talking to your doctor.
Drugs other than those listed here may also interact with venlafaxine. Talk to your doctor and pharmacist before taking any prescription or over-the-counter medicines, including vitamins, minerals, and herbal products.

Where can I get more information?
Your pharmacist has additional information about venlafaxine written for health professionals that you may read.

What does my medication look like?
Venlafaxine is available with a prescription under the brand names Effexor and Effexor XR. Other brand or generic formulations may also be available. Ask your pharmacist any questions you have about this medication, especially if it is new to you.
  • Effexor 25 mg--peach-colored, shield-shaped, scored tablets
  • Effexor 37.5 mg--peach-colored, shield-shaped, scored tablets
  • Effexor 50 mg--peach-colored, shield-shaped, scored tablets
  • Effexor 75 mg--peach-colored, shield-shaped, scored tablets
  • Effexor 100 mg--peach-colored, shield-shaped, scored tablets
  • Effexor XR 37.5 mg-grey/peach capsules
  • Effexor XR 75 mg-peach capsules
  • Effexor XR 150 mg-dark orange capsules

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise.

Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides.

The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.


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