Effexor XR (Venlafaxine HCl): Uses, Dosage, Side Effects, and More

By Jenell Decker, MD
Medically reviewed checkmarkMedically reviewed
February 10, 2020

Effexor XR (venlafaxine HCl) is a medication used to treat a variety of anxiety disorders like generalized anxiety disorder, panic disorder, and social phobia, as well as clinical depression (also referred to as major depressive disorder or MDD). Effexor XR helps to ease depressive symptoms like persistent feelings of sadness, hopelessness, guilt, unworthiness, and lack of interest or enjoyment in things that used to bring you joy. It also can help with symptoms of anxiety like fatigue, nausea and upset stomach, muscular tension and shaking, and feeling restless, jittery, or nervous. The medication works by increasing available levels of the mood-regulating neurotransmitters, serotonin and norepinephrine, in the brain.

What Is Effexor XR?

Effexor XR is an antidepressant and anti-anxiety medication that belongs to the family of selective serotonin and norepinephrine reuptake inhibitors (SNRIs). Effexor XR and other SNRIs improve symptoms of depression and anxiety by increasing available levels of the neurotransmitters serotonin and norepinephrine in the brain.

Talk to a doctor online

Refill medications and get certain necessary prescriptions.

Start now

Effexor XR Generic Name

Effexor XR is the brand name for venlafaxine hydrochloride extended-release.

The generic form of Effexor, venlafaxine, was approved for medical use in the United States in 1993. Originally, Effexor was only available as an immediate release tablet, which means that it had a short half life. This required a person to take it several times a day to keep adequate levels in the body for therapeutic use.

In 1997, an extended release capsule, Effexor XR, became available in the United States. Effexor was discontinued in favor of Effexor XR, which caused less nausea and could be taken just once daily instead of multiple times. Effexor XR is now available in generic as venlafaxine hydrochloride extended-release.

Venlafaxine Uses

Venlafaxine is mainly used to treat:

In addition to these main uses, venlafaxine has also been used to treat:

  • Post-traumatic stress disorder
  • Hot flashes caused by menopause and chemotherapy
  • Nerve pain in those with diabetes
  • Migraines and tension headaches
  • Chronic fatigue syndrome
  • Bipolar depression
  • Attention-deficit hyperactivity disorder (ADHD)

How Does Venlafaxine Work?

Venlafaxine is a serotonin and norepinephrine reuptake inhibitor (SNRI). This class of medication works by preventing the reuptake of the neurotransmitters serotonin and norepinephrine by nerve cells, which increases their available levels in the brain. These neurotransmitters are important in the regulation of mood and energy levels. When levels of available serotonin and norepinephrine in the brain are too low, people can feel depressed, anxious, and experience low energy and pain from nerves and muscles.

Before You Take Venlafaxine

There are some health conditions and behaviors that could interfere with the effectiveness or safety of venlafaxine. Before beginning treatment, let your doctor know if you currently have or have had:

  • Allergies to venlafaxine or desvenlafaxine (Pristiq)
  • Problems with bleeding or clotting
  • Family or personal history of narrow-angle glaucoma
  • Bipolar disorder
  • Liver or kidney disease
  • High blood pressure or cholesterol
  • Heart problems
  • Diabetes
  • Thyroid disorder
  • Seizures
  • Low blood levels of sodium

There are also certain drug interactions that can change how venlafaxine works, and can increase the likelihood of serious side effects. Some common drug contraindications (things you should not take while on venlafaxine) include:

  • Nonsteroidal anti-inflammatory drugs (NSAIDs): Such as aspirin (Tylenol), ibuprofen (Advil, Motrin), or naproxen (Aleve).
  • Blood thinners: Such as warfarin.
  • Antiplatelet drugs: Such as clopidogrel.
  • MAOIs: A dangerous drug interaction can occur between venlafaxine and monoamine oxidase inhibitors (MAOIs) like isocarboxazid, linezolid, and methylene blue. To prevent an interaction between drugs, do not use venlafaxine within seven days before you plan to use an MAOI, or 14 days after you have used an MAOI.
  • Substances that increase serotonin: Such as MDMA (ecstasy), the herb St. John’s wort, other antidepressants in the SSRI or SNRI family, or the supplement tryptophan.
  • Drugs that cause drowsiness: Such as cough medicines, opioid pain medications, alcohol, marijuana, sleep or anxiety medicines, muscle relaxants, and antihistamines.

This is a list of only the most common contraindications. A more comprehensive list of the of 609 drugs that interact with venlafaxine can be found here.

Avoid driving or operating heavy machinery until you know how venlafaxine will affect you. It may cause impaired reactions, dizziness, or fainting, especially in the beginning of treatment before your body is used to the medication.

Talk to your doctor before switching to venlafaxine from another antidepressant. Also, if you are breastfeeding or pregnant, talk to your doctor about the benefits and risks of taking this medication. Always tell your doctor or dentist that you take venlafaxine, and any other medications, before having surgery.

If you’re undergoing a urine drug test, taking this medicine can give you a false positive. Let the person ordering the test and laboratory staff know that you’re taking venlafaxine.

Venlafaxine Dosage

Your doctor will base your dosage on your medical condition and response to treatment. Usually, to reduce the risk of side effects, you’ll begin the medication at a low dose and gradually work your way up.

Venlafaxine is usually started at 37.5 mg per day for about a week before increasing to 75 mg daily.

Every four or five days, your doctor may instruct you to take a little more, to find your therapeutic dose, which can be around 150 mg per day. In most outpatient settings, the maximum dose is 225 mg per day. Inpatient settings can prescribe up to 350 mg per day.

Common dosages for venlafaxine treatment, taken once daily are:

It’s important to take venlafaxine exactly as your health care provider prescribes it. To avoid nausea and other gastric side effects, venlafaxine should be taken with food. If possible, it’s best to take it at the same time every day.

Don’t chew, crush, or dissolve the venlafaxine capsule. If you find it hard to swallow, you can open the capsule and sprinkle the contents into a small amount of food like yogurt or applesauce. Swallow the mixture without chewing it, and consume it right away, not saving any for later.

How long does it take for venlafaxine to kick in?

It’s normal for it to take several weeks before you feel improvements in your symptoms after beginning venlafaxine. It’s important to take this medication as prescribed even if at first you feel side effects or don’t feel any benefits. Stopping taking it suddenly can cause anxiety, fatigue, headache, diarrhea, sleep disturbances, and other side effects. After several weeks, side effects often subside and benefits become more noticeable.

What happens if I miss a dose?

If you miss a dose, take it as soon as you remember. However, if it’s almost time for your next dose, just skip the missed dose and take your next one as normal. You should not take both doses at once to make up for the missed one. You can always contact your doctor or pharmacist if you have questions about a missed dose.

Can you stop venlafaxine cold turkey? Does venlafaxine cause withdrawal symptoms?

If you want to stop the medication, it’s important to work with your doctor to gradually taper yourself off over at least two weeks. Stopping suddenly or too quickly can cause very uncomfortable withdrawal effects including:

  • Insomnia
  • Anxiety and agitation
  • Dizziness
  • Nausea, vomiting, and diarrhea
  • Irritability
  • Headache and shock-like symptoms in head
  • Anorexia
  • Confusion and impaired coordination and balance
  • Flu-like symptoms
  • Nightmares
  • Tinnitus
  • Seizures

Talk to a doctor online

Refill medications and get certain necessary prescriptions.

Start now

Common Side Effects

While side effects can seem daunting, most people experience mild side effects, if any at all. Beginning a new medication can be scary, but if your doctor has prescribed venlafaxine to you, she or he believes that potential benefits outweigh potential risks. Starting the medication at a very low dose, taken twice daily, and building up to a therapeutic dose slowly, can help you avoid side effects.

The most common side effects of venlafaxine are:

  • Dizziness
  • Blurred vision
  • Fatigue
  • Dry mouth
  • Insomnia or difficulty falling asleep
  • Gastrointestinal issues like heartburn, decreased appetite, constipation, gas, or diarrhea
  • Vivid or unusual dreams
  • Chills
  • Decreased sex drive or difficulty achieving orgasm or ejaculation
  • Sweating
  • Prickly or tingling sensations
  • Weight loss

Less frequently, people can experience:

  • Muscular tension
  • Increased yawning
  • Change in taste
  • Night sweats

Venlafaxine can increase blood pressure, so your blood pressure will be checked regularly while you’re on this medication.

It’s very rare, but a serious allergic reaction to venlafaxine is possible. If you have an allergic reaction while on this medication, get medical attention right away. Symptoms of a serious allergic reaction include:

Adults over the age of 65 can be more susceptible to bleeding disorders, dizziness, lightheadedness, coordination issues, or fainting, all of which can increase the risk of falling. Older adults, especially those taking diuretics, can also develop hyponatremia, which is an imbalance of sodium levels in your blood. Talk to your doctor if you are concerned about the safety of yourself or an older adult taking this medication.

Some people, particularly those between the ages of 18-24 years old who have major depressive disorder (MDD), can have thoughts about suicide when first taking this or other antidepressants. Let your doctor know if your symptoms worsen or if you have suicidal thoughts or behaviors. If you have a child beginning venlafaxine, monitor them for any changes in mood or symptoms. Children under 18 years old can also lose their appetites and lose weight. Make sure to monitor your child’s food intake and weight if they are taking venlafaxine.

If you’re having a mental health emergency, call 911 or go to the nearest emergency room. You can also get free 24/7 support from a suicide and crisis expert by calling or texting 988. If you’d prefer to chat online, you can chat with a suicide and crisis expert by visiting the Lifeline Chat.

Venlafaxine Alternatives

Venlafaxine belongs to the class of medications called selective serotonin and norepinephrine reuptake inhibitors (SNRIs). These antidepressants are used for treating anxiety, depression, and chronic pain. For some people, a different medication in the same family can be more helpful and cause fewer side effects. If venlafaxine doesn’t work for you, you can try another SNRI like:

  • Milnacipran (Savella)
  • Desvenlafaxine (Pristiq)
  • Duloxetine (Cymbalta)

Effexor XR vs. Zoloft

If you want to try a different type of medication for anxiety and depression that still works with increasing available serotonin in the brain, you can try a medication that belongs to the family of selective serotonin reuptake inhibitors (SSRIs) such as Zoloft. These medications prevent the reuptake of serotonin after it has been released, increasing available serotonin in the brain. These medications can be very effective for treating anxiety and depression, and they might have fewer side effects than SNRIs, but they don’t treat chronic pain the way SNRIs do. These include:

Effexor XR vs. Wellbutrin

While Effexor XR and Wellbutrin are both used as antidepressants, the way they work, and the conditions they treat can differ. In addition to depression, Effexor XR is mostly used to treat anxiety disorders. Wellbutrin also treats depression, but it is not an effective treatment for anxiety or panic disorders. In addition to depression, Wellbutrin is used to help people stop smoking, as an appetite suppressant, and can treat symptoms of attention deficit hyperactivity disorder (ADHD) and seasonal affective disorder (SAD). In addition to what they treat, the way they work differs.

Effexor XR is a selective serotonin and norepinephrine reuptake inhibitor (SNRI), which works by increasing available levels of norepinephrine and serotonin in the brain. Wellbutrin is a norepinephrine-dopamine reuptake inhibitor (NDRI), which works by boosting levels of available norepinephrine and dopamine in the brain. Effexor XR and Wellbutrin also have different side effects. For example, Wellbutrin is known to cause fewer sexual side effects and to be safer for pregnancy, while Effexor XR carries a smaller risk for seizures at high doses.

Talk to a doctor online

Refill medications and get certain necessary prescriptions.

Start now

When to See a Doctor

Let your doctor know if your symptoms are not improving after several weeks, or if they are getting worse. Also contact your doctor if side effects are interfering with your everyday life–there are other, similar medications you can try that might work better for you with fewer side effects.

Although it’s rare, this medication and other medications that increase serotonin can cause serotonin syndrome. This is a very serious condition that requires immediate medical attention. Seek medical attention if you experience:

  • Hallucinations
  • Fever
  • Sweating
  • Shivering
  • Rapid heart rate
  • Uncontrolled muscular stiffness or twitching
  • Unusual agitation or restlessness
  • Nausea and vomiting
  • Black, bloody stool
  • Loss of coordination

You should also seek emergency medical attention or contact your doctor if you notice any of these symptoms:

  • Persistent cough
  • Shortness of breath and chest pain
  • Vision changes such as widened pupils, tunnel vision, blurred vision, seeing halos around lights, or eye swelling or pain
  • Easy bruising
  • Unusual bleeding like nosebleeds, bleeding gums, coughing up blood, or bloody urine or stool
  • Headache
  • Confusion
  • Slurred speech
  • Severe weakness and loss of coordination
  • Seizure
  • Black or bloody stool
  • Vomit that looks like coffee grounds
  • Stiff and rigid muscles with tremors
  • Fast or uneven heartbeats

If you suspect an overdose, seek emergency medical attention (by calling 911), or call the poison help line at 1-800-222-1222. Symptoms of an overdose can include:

  • Seizures
  • Fainting
  • Severe drowsiness
  • Rapid heart rate
  • Coma

Antidepressants like venlafaxine can increase your risk of suicidal thoughts and behavior, especially in children and adolescents between the ages of 18-24 with major depressive disorder. If you or your children under 24 years notice mood changes or suicidal ideation, especially in the beginning of treatment, notify your doctor or seek medical attention right away.

K Health offers K Therapy, a text-based therapy program that includes unlimited messaging with a licensed therapist, plus free resources designed by mental health experts to use on your own.

How K Health Can Help

Think you might need a prescription for Effexor (Venlafaxine)?

K Health has clinicians standing by 24/7 to evaluate your symptoms and determine if Effexor is right for you.

Get started with our free assessment, which will tell you in minutes if treatment could be a good fit. If yes, we’ll connect you right to a clinician who can prescribe medication and have it shipped right to your door.

K Health articles are all written and reviewed by MDs, PhDs, NPs, or PharmDs and are for informational purposes only. This information does not constitute and should not be relied on for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment.

Jenell Decker, MD

Dr. Decker is a family medicine physician who completed her residency at East Carolina University School of Medicine. She graduated medical school from Marshall University School of Medicine.

Close button

Refill medications and get certain necessary prescriptions with K Health from home.

Start Now
Image of pill bottle