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Depression & Anxiety



Brand Names: Effexor, Effexor XR
Drug Class: Antidepressant
Available in: Tablets, extended-release capsules
Available OTC? No
As Generic? No

Side Effects

Serious: Headache, changes in or blurred vision, decreased sexual ability or desire, difficulty urinating, itching, skin rash, chest pain, heartbeat irregularities, changes in moods or mental state, extreme drowsiness or fatigue. Call your physician immediately.

Common: Fatigue, dizziness or drowsiness, anxiety, dry mouth, changed sense of taste, loss of appetite, nausea, vomiting, chills, diarrhea, constipation, prickly sensation of skin, heartburn, increased sweating, runny nose, stomach gas or pain, insomnia, unusual dreams, weight loss.

Less Common: Frequent yawning, twitching.

Principal Uses

To treat symptoms of major depression and generalized anxiety disorder (GAD).

How the Drug Works

Venlafaxine helps to balance levels of serotonin and norepinephrine, brain chemicals that are profoundly linked to mood, emotions, and mental state.


Tablets: Adults: To start, 75 mg a day in 2 or 3 divided doses. The dose may be gradually increased by your doctor to 375 mg a day.

Extended-release capsules: To start, 75 mg, once a day. The dose may be increased by up to 75 mg at a time at intervals of not less than 4 days, up to a maximum dose of 225 mg a day.

Onset of Effect

2 weeks or more.

Duration of Action


Dietary Advice

Venlafaxine should be taken with meals.


Store in a tightly sealed container away from heat, moisture, and direct light.

If You Miss a Dose

Tablets: Take it as soon as you remember, unless the time for your next scheduled dose is within the next 2 hours. If so, skip the missed dose, take the next scheduled dose, and resume your regular schedule. Do not double the next dose.

Extended-release capsules: If you miss a dose on one day, do not double the dose the next day.

Stopping the Drug

Take this medication as prescribed for the full treatment period, even if you begin to feel better before the scheduled end of therapy.

Prolonged Use

See your doctor regularly for tests and examinations if you must take this medicine for a prolonged period.


Over 60: No special problems are expected.

Driving and Hazardous Work: Do not drive or engage in hazardous work until you determine how the medicine affects you.

Alcohol: Avoid alcohol.

Pregnancy: Adequate studies of venlafaxine use during pregnancy have not been done. Before you take venlafaxine, tell your doctor if you are pregnant or plan to become pregnant.

Breast Feeding: It is not known whether venlafaxine passes into breast milk; caution is advised. Consult your doctor for specific advice.

Infants and Children: The safety and effectiveness of venlafaxine use by infants and children have not been established.

Special Concerns: Venlafaxine can cause an elevation in blood pressure. Therefore, blood pressure should be monitored regularly, especially in the first several months of therapy.


Symptoms: Extreme drowsiness or fatigue.

What to Do: Call your doctor, emergency medical services (EMS), or the nearest poison control center immediately.

Drug Interactions

Venlafaxine and MAO inhibitors should not be used within 14 days of each other. Serious side effects such as myoclonus (uncontrolled muscle spasms), hyperthermia (excessive rise in body temperature), and extreme stiffness may result. Consult your doctor for specific advice if you are taking any other prescription or over-the-counter medication.

Food Interactions

No known food interactions.

Disease Interactions

Consult your physician if you have a history of any of the following: high or low blood pressure, alcohol or drug abuse, heart disease, or seizures. Use of venlafaxine may cause complications in patients with liver or kidney disease, since these organs work together to remove the medication from the body.

From The Johns Hopkins Consumer Guide to Drugs. You can order this book now on our secure server.


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