Effexor

DRUG DESCRIPTION

Effexor (venlafaxine hydrochloride) is a structurally novel antidepressant for oral administration. It is designated (R/S)-1-[2-(dimethylamino)-1-(4-methoxyphenyl)ethyl] cyclohexanol hydrochloride or (±)-1-[?-[(dimethyl-amino)methyl]-p-methoxybenzyl] cyclohexanol hydrochloride and has the empirical formula of C17H27NO2 HCl. Its molecular weight is 313.87. The structural formula is shown below.

Effexor®
(venlafaxine hydrochloride) Formula Illustration

Venlafaxine hydrochloride is a white to off-white crystalline solid with a solubility of 572 mg/mL in water (adjusted to ionic strength of 0.2 M with sodium chloride). Its octanol:water (0.2 M sodium chloride) partition coefficient is 0.43.

Compressed tablets contain venlafaxine hydrochloride equivalent to 25 mg, 37.5 mg, 50 mg, 75 mg, or 100 mg venlafaxine. Inactive ingredients consist of cellulose, iron oxides, lactose, magnesium stearate, and sodium starch glycolate.

What are the possible side effects of venlafaxine (Effexor, Effexor XR)?

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.

Contact your doctor promptly if you have any of the following side effects, especially if they are new symptoms or if they get worse: mood changes, anxiety, panic attacks, trouble sleeping, irritability, agitation, aggressiveness, severe restlessness, mania (mental and/or physical hyperactivity), thoughts of suicide or hurting yourself.

Call your doctor...

Read All Potential Side Effects and See Pictures of Effexor »

What are the precautions when taking venlafaxine hydrochloride (Effexor)?

Before taking venlafaxine, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: bleeding problems, glaucoma, high blood pressure, heart problems (such as heart failure, previous heart attack), high cholesterol, kidney disease, liver disease, seizure disorder, thyroid disease.

This drug may make you dizzy or drowsy or cause blurred vision. Do not drive, use machinery, or do any activity that requires alertness or clear vision until you are sure you can perform such activities safely. Avoid...

Read All Potential Precautions of Effexor »


Effexor Consumer (continued)

SIDE EFFECTS: See also Warning section.

Nausea, drowsiness, dizziness, dry mouth, constipation, loss of appetite, blurred vision, nervousness, trouble sleeping, unusual sweating, or yawning may occur. If any of these effects persist or worsen, tell your doctor promptly.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if any of these unlikely but serious side effects occur: easy bruising/bleeding, decreased interest in sex, changes in sexual ability, muscle cramps/weakness, shaking (tremor).

Get medical help right away if any of these rare but serious side effects occur: black/bloody stools, persistent cough, seizure, severe/pounding headache, shortness of breath, vomit that looks like coffee grounds.

This medication may rarely cause a very serious condition called serotonin syndrome. The risk increases when this medication is used with certain other drugs (see Drug Interactions section). Get medical help right away if you develop some of the following symptoms: hallucinations, unusual restlessness, loss of coordination, fast heartbeat, severe dizziness, unexplained fever, severe nausea/vomiting/diarrhea, twitching muscles.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

PRECAUTIONS: Before taking venlafaxine, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: bleeding problems, glaucoma, high blood pressure, heart problems (such as heart failure, previous heart attack), high cholesterol, kidney disease, liver disease, seizure disorder, thyroid disease.

This drug may make you dizzy or drowsy or cause blurred vision. Do not drive, use machinery, or do any activity that requires alertness or clear vision until you are sure you can perform such activities safely. Avoid alcoholic beverages.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Older adults may be at greater risk for bleeding while taking this drug. Older adults may also be more likely to develop a type of salt imbalance (hyponatremia), especially if they are taking "water pills" (diuretics).

Children may be more sensitive to the side effects of the drug, especially loss of appetite and weight loss. Monitor weight and height in children who are taking this drug.

During pregnancy, this medication should be used only when clearly needed. It may harm an unborn baby. Also, babies born to mothers who have used this drug during the last 3 months of pregnancy may infrequently develop withdrawal symptoms such as feeding/breathing difficulties, seizures, muscle stiffness, or constant crying. If you notice any of these symptoms in your newborn, tell the doctor promptly.

Since untreated depression can be a serious condition, do not stop taking this medication unless directed by your doctor. If you are planning pregnancy, become pregnant, or think you may be pregnant, immediately discuss the benefits and risks of using this medication during pregnancy with your doctor.

This drug passes into breast milk and may have undesirable effects on a nursing infant. Consult your doctor before breast-feeding.


Effexor Patient Information Including Side Effects

Brand Names: Effexor, Effexor XR

Generic Name: venlafaxine (Pronunciation: VEN la fax een)

  • What is venlafaxine (Effexor)?
  • What are the possible side effects of venlafaxine (Effexor)?
  • What is the most important information I should know about venlafaxine (Effexor)?
  • What should I discuss with my healthcare provider before taking venlafaxine (Effexor)?
  • How should I take venlafaxine (Effexor)?
  • What happens if I miss a dose (Effexor)?
  • What happens if I overdose (Effexor)?
  • What should I avoid while taking venlafaxine (Effexor)?
  • What other drugs will affect venlafaxine (Effexor)?
  • Where can I get more information?

What is venlafaxine (Effexor)?

Venlafaxine is an antidepressant in a group of drugs called selective serotonin and norepinephrine reuptake inhibitors (SSNRIs). Venlafaxine affects chemicals in the brain that may become unbalanced and cause depression.

Venlafaxine is used to treat major depressive disorder, anxiety, and panic disorder.

Venlafaxine may also be used for other purposes not listed in this medication guide.

What are the possible side effects of venlafaxine (Effexor)?

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.

Contact your doctor promptly if you have any of the following side effects, especially if they are new symptoms or if they get worse: mood changes, anxiety, panic attacks, trouble sleeping, irritability, agitation, aggressiveness, severe restlessness, mania (mental and/or physical hyperactivity), thoughts of suicide or hurting yourself.

Call your doctor at once if you have any of these serious side effects:

  • increased blood pressure (severe headache, blurred vision);
  • easy bruising or bleeding;
  • severe blistering, peeling, and red skin rash;
  • very stiff (rigid) muscles, high fever, sweating, fast or uneven heartbeats, tremors, overactive reflexes;
  • nausea, vomiting, diarrhea, loss of appetite, feeling unsteady, loss of coordination; or
  • headache, trouble concentrating, memory problems, weakness, confusion, hallucinations, fainting, seizure, shallow breathing or breathing that stops.

Less serious side effects may include:

  • drowsiness, dizziness, feeling nervous;
  • dry mouth;
  • mild nausea, constipation;
  • decreased sex drive, impotence, or difficulty having an orgasm;
  • blurred vision;
  • increased appetite; or
  • changes in weight.

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.

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

Do not take this medication if you are allergic to venlafaxine, or if you are also using a monoamine oxidase inhibitor (MAOI) such as isocarboxazid (Marplan), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Emsam), or tranylcypromine (Parnate).

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.

Avoid drinking alcohol, which can increase some of the side effects of venlafaxine.

It may take 4 weeks or more for your symptoms to improve. For best results, keep using the medication as directed. Do not stop using venlafaxine without first talking to your doctor. You may have unpleasant side effects if you stop taking this medication suddenly.

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  • Effexor
  • Effexor XR


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