Switching From Effexor® to Cymbalta®

Kristin Hall

Reviewed by Kristin Hall, FNP

Written by Nicholas Gibson

Published 06/20/2022

Updated 06/21/2022

Effexor® and Cymbalta® are prescription medications that are used to treat major depression and certain anxiety disorders.

If you’ve been diagnosed with major depressive disorder (MDD), generalized anxiety disorder (GAD) or a related condition, your healthcare provider may suggest using either medication to treat your symptoms and improve your quality of life.

It’s common to switch antidepressants, and in certain circumstances, your healthcare provider may recommend switching from Effexor to Cymbalta.

Below, we’ve explained what Effexor and Cymbalta are, as well as why you may need to make the switch from one medication to the other.

We’ve also discussed how you can change medications without increasing your risk of adverse effects or withdrawal symptoms. 

Effexor is an antidepressant medication that contains the ingredient venlafaxine. It belongs to a class of medications called serotonin-norepinephrine reuptake inhibitors, or SNRIs.

As Effexor XR®, venlafaxine is currently approved by the Food and Drug Administration (FDA) to treat major depression, social anxiety disorder (SAD), panic disorder (PD) and generalized anxiety disorder.

Venlafaxine works by increasing levels of the neurotransmitters serotonin and norepinephrine in your brain and body.

Serotonin is a neurotransmitter that’s primarily involved in regulating your feelings of happiness, anxiety and general moods. Low levels of serotonin are linked to depression, anxiety and sleep issues such as insomnia.

Norepinephrine, or noradrenaline, is involved in managing your attention, sleep-wake cycle and ability to create memories. Low levels of norepinephrine are also linked to mental health issues, including depression, attention deficit hyperactivity disorder (ADHD) and lack of focus.

SNRI medications like Effexor may help to treat depression and anxiety disorders by increasing your levels of serotonin and norepinephrine. 

Cymbalta is an antidepressant that contains the active ingredient duloxetine. Like Effexor, it’s a serotonin-norepinephrine reuptake inhibitor that works by increasing levels of neurotransmitters in your brain and body.

Currently, Cymbalta is approved by the FDA to treat major depression, as well as some types of anxiety and chronic pain, including:

  • Generalized anxiety disorder

  • Fibromyalgia (FM)

  • Diabetic peripheral neuropathic pain (DPNP)

  • Chronic musculoskeletal pain

Our guide to depression medications provides more information about how antidepressants like Effexor, Cymbalta and others work. 

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Antidepressants such as Effexor and Cymbalta are usually effective at treating depression and anxiety. However, many people try multiple antidepressants before finding the right one for their symptoms and personal needs.

If you’re prescribed Effexor, it may take several weeks for your medication to start working. It’s normal for antidepressants to start working gradually, and for many people, symptoms such as sleep difficulties or concentration improve before mood.

If you don’t notice any improvements from Effexor after four weeks or more, or if you have side effects that are persistent or bothersome, your healthcare provider may suggest switching from Effexor to a different SNRI, such as Cymbalta.

There are several ways to switch antidepressants:

  • Cross-tapering. Cross-tapering involves gradually reducing the dosage of your original antidepressant while increasing the dosage of your new medication. This allows you to switch antidepressants without ever going without medication.

  • Tapering your dosage. This involves reducing the dosage of your original medication, then starting the new medication at a low dose. The tapering process may help to lower your risk of developing antidepressant withdrawal.

  • Direct switching. This approach involves switching directly from one antidepressant to another, without any tapering or “wash-out” period. 

When switching from Effexor to Cymbalta, the recommended technique is to slowly taper your dosage, then start treatment with the new antidepressant at a low dose.

Your healthcare provider will inform you about how to taper your dosage of Effexor. Make sure to follow their instructions and gradually reduce your dosage over time, then start Cymbalta at the prescribed dosage.

It’s important not to stop taking Effexor without tapering, as doing so can increase your risk of experiencing withdrawal symptoms.

Common symptoms of abrupt withdrawal of Effexor include:

  • Anxiety

  • Agitation

  • Confusion

  • Tiredness

  • Headache

  • Dizziness

  • Mood changes

  • Abnormal excitement

  • Lack of coordination

  • Loss of appetite

  • Difficulty sleeping

  • Blurred vision

  • Ringing in the ears

  • Irritability

  • Nightmares

  • Nausea

  • Vomiting

  • Diarrhea

  • Dry mouth

  • Sweating

  • Shaking

  • Numbness

  • Tingling

These symptoms can begin within hours or days of dose reduction. Compared to other popular antidepressants, Effexor (and its generic, venlafaxine) is generally associated with more severe withdrawal symptoms.

If you experience any withdrawal symptoms while switching from Effexor to Cymbalta, tell your healthcare provider as soon as you can. They may suggest adjusting your dosage of Effexor or slowing down the tapering process to give the drug more time to exit your body gradually. 

To learn about Effexor and another common antidepressant, check out our article: Effexor vs Zoloft: What Are The Differences?

Effexor and Cymbalta can both cause side effects, some of which may develop shortly after you start treatment. Many of the side effects of Effexor and Cymbalta are temporary, although some may persist for several weeks or months after starting treatment.

Common side effects of Effexor include:

  • Nausea

  • Dizziness

  • Vomiting

  • Diarrhea

  • Constipation

  • Difficulty sleeping

  • Physical weakness

  • Anorexia

  • Dry mouth

  • High blood pressure

  • Heart palpitations

  • Vasodilation

  • Paresthesia (burning or prickling sensation)

  • Sweating, including night sweats

  • Somnolence (drowsiness)

  • Abnormal vision

Like other antidepressants, Effexor can cause sexual side effects, including a reduced sex drive, difficulty reaching orgasm and, in men, erectile dysfunction (ED).

Common side effects of Cymbalta include:

  • Nausea

  • Dry mouth

  • Diarrhea

  • Constipation

  • Abdominal pain

  • Vomiting

  • Fatigue

  • Decreased appetite

  • Weight loss

  • Dizziness

  • Somnolence (drowsiness)

  • Abnormal dreams

  • Tremor

  • Agitation

  • Anxiety 

  • Insomnia

  • Heart palpitations

Cymbalta can also cause or contribute to sexual dysfunction, including a reduced interest in sex and difficulty achieving orgasm. In men, Cymbalta may cause or contribute to ejaculation disorder and erectile dysfunction. 

Effexor and Cymbalta can both interact with other medications. When used with medications or substances that increase serotonin levels, both Effexor and Cymbalta can potentially contribute to a serious condition called serotonin syndrome.

Serotonin syndrome occurs when your serotonin levels increase beyond a safe level. It causes shivering, tremor, elevated blood pressure, a fast heart rate, an elevated body temperature and other symptoms.

When severe, serotonin syndrome can result in seizures, metabolic acidosis, renal failure, acute respiratory distress syndrome, coma and even death.

You have a significant risk of serotonin syndrome if you take Effexor or Cymbalta with any other medications or substances that increase serotonin levels, including:

It’s important to inform your healthcare provider about any medications and dietary supplements you currently use or have recently used before using Effexor or Cymbalta.

Your healthcare provider will inform you if you need to stop using any medications while starting treatment with Effexor or Cymbalta or switching from one medication to the other.

Learn the differences between Effexor and another popular antidepressant here: Effexor vs Zoloft: What Are The Differences?

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Effexor and Cymbalta are both effective, proven medications for treating depression and certain forms of anxiety. 

Your healthcare provider may recommend switching from Effexor to Cymbalta if you don’t notice any improvements in your moods or other depression symptoms, or if you have side effects that don’t get better over time.

Follow your healthcare provider’s instructions to switch successfully, and make sure to tell them if you start to experience any side effects.

For most people, the process of switching from Effexor to Cymbalta (or switching from Cymbalta to Effexor, in some cases) is a smooth one. 

Interested in using medication to treat depression or anxiety? We offer a full selection of mental health services online, including the ability to connect with a licensed psychiatry provider and, if appropriate, access depression and anxiety medication

You can also learn more about successfully dealing with depression, anxiety, chronic stress and other mental health concerns using our free mental health resources and content. 

8 Sources

Hims & Hers has strict sourcing guidelines to ensure our content is accurate and current. We rely on peer-reviewed studies, academic research institutions, and medical associations. We strive to use primary sources and refrain from using tertiary references.

  1. EFFEXOR XR® (venlafaxine Extended-Release) Capsules. (2017, January). Retrieved from
  2. Venlafaxine. (2022, January 15). Retrieved from
  3. Brain Hormones. (2022, January 23). Retrieved from
  4. Adrenal Hormones. (2022, January 23). Retrieved from
  5. Duloxetine. (2022, March 15). Retrieved from
  6. Cymbalta (duloxetine hydrochloride) Delayed-Release Capsules for Oral Use. (2010, October). Retrieved from
  7. Keks, N., Hope, J. & Keogh, S. (2016, June). Switching and stopping antidepressants. Australian Prescriber. 39 (3), 76-83. Retrieved from
  8. Volpi-Abadie, J., Kaye, A.M. & Kaye, A.D. (2013). Serotonin Syndrome. The Ochsner Journal. 13 (4), 533-540. Retrieved from

This article is for informational purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment. Learn more about our editorial standards here.

Kristin Hall, FNP

Kristin Hall is a board-certified Family Nurse Practitioner with decades of experience in clinical practice and leadership. 

She has an extensive background in Family Medicine as both a front-line healthcare provider and clinical leader through her work as a primary care provider, retail health clinician and as Principal Investigator with the NIH

Certified through the American Nurses Credentialing Center, she brings her expertise in Family Medicine into your home by helping people improve their health and actively participate in their own healthcare. 

Kristin is a St. Louis native and earned her master’s degree in Nursing from St. Louis University, and is also a member of the American Academy of Nurse Practitioners. You can find Kristin on LinkedIn for more information.

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