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8 Cymbalta Side Effects: Should I be Concerned?

Medically reviewed by Carmen Pope, BPharm. Last updated on May 11, 2023.

Official answer

by Drugs.com

Cymbalta is used to treat depression, anxiety, and some pain syndromes. But what are the risks associated with this drug? Do most people who start it realize how hard it may be to stop?

1. Cymbalta May Be Difficult to Stop

Most antidepressant drugs are associated with some withdrawal symptoms. However, withdrawal symptoms from Cymbalta are so common that doctors have given the symptoms the term: Cymbalta Discontinuation Syndrome.

Hundreds of lawsuits have been filed against Eli Lilly, the makers of Cymbalta, claiming that consumers and healthcare professionals nationwide were not fully and accurately informed of the frequency, severity, and duration of Cymbalta's withdrawal when it first entered the market in 2004.

Some research has indicated that serious symptoms of withdrawal may be experienced by up to 51% of people who discontinue Cymbalta, yet when the medication was first marketed, the manufacturer Eli Lilly and Co reported the withdrawal rate as about 1%.

2. Withdrawal Effects Can Be Severe

Withdrawal effects vary individually. Some experts estimate roughly 50% of people discontinuing Cymbalta will have withdrawal symptoms.

Minor withdrawal symptoms include nausea, headache, and dizziness. Severe symptoms include seizures, nightmares, and electrical shock sensations (described by some as "zaps" around your body, which may be paresthesias).

These effects can last for weeks and may force some people to restart therapy before a more gradual discontinuation. The FDA instructed Eli Lilly to be more transparent in their delivery of benefits vs. risks for Cymbalta and to recommend a protocol for stopping Cymbalta.

3. Increased Risk of Suicidal Thoughts Possible

Studies have shown an association between antidepressant treatment (including Cymbalta-like antidepressants) and an increased risk of suicidal thoughts and behavior, particularly in people under 25 years of age and more often in the early phases of treatment.

Regardless of age, all patients who are started on Cymbalta should be monitored for a worsening of their depression or the emergence of suicidal thoughts and behaviors. See a doctor right away if there is any cause for concern.

On the flip side, many people report that Cymbalta was the only thing that lifted them out of the "fog" they were in or prevented them from yet another hospital visit.

4. Short-Term Memory Loss and Brain Fog

Although studies have not reported any detrimental effects on brain function and memory, some blogs tell a different story.

A lack of short-term memory, difficulty concentrating, and brain zaps are just some of the complaints experienced by people taking Cymbalta.

Do not drive or operate machinery if Cymbalta makes you drowsy or sedated, or until you are reasonably certain the drug does not affect your ability to do these things.

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5. Anger and Hostility Reported

Although Cymbalta is often used for anxiety, in some people it may have the opposite effect and cause tension and restlessness. Some people may find themselves more frustrated, irritable, or lacking in patience when taking the drug. Occasionally this can escalate to open hostility towards others, extreme agitation, and even mania. These effects may be more apparent early on in treatment or after discontinuation.

Try relaxation techniques to calm you down. If these do not make any difference or you feel your symptoms are unbearable or getting worse you may need to discuss changing your medicine with a doctor.

6. Side Effects Include Extreme Sweating

Hyperhidrosis (excessive sweating) is another common side effect of Cymbalta, occurring in over 7 percent of patients. Reports of soaking through T-shirts 24 hours a day, or extremely sweaty palms or feet may force treatment discontinuation in some people.

Cymbalta may also cause vision changes, a dry mouth, and nausea and interact with several other drugs. It is also not suitable for some people with liver disease, bleeding or seizure disorders, or high blood pressure.

7. Leg Jerks, Muscle Twitches, and Rarely Seizures

Seizures are listed as a rare but serious side effect of Cymbalta, occurring in roughly 3 out of every 10,500 patients. But more subtle effects, such as restless legs, muscle twitches or spasms, or leg jerks may be experienced by a larger number of people.

Some notice these effects after they have been on Cymbalta for a while, whereas others report these effects on discontinuation. People who already have a seizure disorder may be at greater risk of having a seizure while taking Cymbalta.

8. Loss of Sex Drive Can Occur With Most Antidepressants

Many antidepressants have detrimental effects on sexual function and Cymbalta is no exception. Males are more likely to be affected and decreases in libido, abnormal orgasms, and erectile dysfunction have all been reported.

Most effects disappeared with treatment discontinuation. If sexual dysfunction occurs while you are taking an antidepressant like Cymbalta, be sure to talk to your doctor who may suggest an alternative treatment.

Bupropion (Wellbutrin), trazodone (Desyrel), or nefazodone (Serzone) are less likely to cause sexual dysfunction.

References
  • Cymbalta (duloxetine) [Package Insert] Eli Lilly and Company Reviewed 09/2021 https://www.drugs.com/pro/cymbalta.html
  • Bitter I, Filipovits D, Czobor P. Adverse reactions to duloxetine in depression. Expert Opin Drug Saf. 2011 Nov;10(6):839-50. doi: 10.1517/14740338.2011.582037. Epub 2011 May 5.
  • Perahia DG, Kajdasz DK, Desaiah D, Haddad PM. Symptoms following abrupt discontinuation of duloxetine treatment in patients with major depressive disorder. J Affect Disord. 2005 Dec;89(1-3):207-12. Epub 2005 Nov 2.
  • Perahia DG1, Kajdasz DK, Desaiah D, et al. Symptoms following abrupt discontinuation of duloxetine treatment in patients with major depressive disorder. J Affect Disord. 2005 Dec;89(1-3):207-12. Epub 2005 Nov 2. http://www.ncbi.nlm.nih.gov/pubmed/16266753
  • Nischal A, Tripathi A, Nischal A, Trivedi JK. Suicide and Antidepressants: What Current Evidence Indicates. Mens Sana Monographs. 2012;10(1):33-44. doi:10.4103/0973-1229.87287.
  • Depression and Antidepressants: Options, Advantages, and Precautions. July 2022. https://www.drugs.com/article/antidepressants.html
  • Norman TR, Olver JS. Duloxetine in the treatment of generalized anxiety disorder. Neuropsychiatr Dis Treat. 2008 Dec;4(6):1169-80.
  • Cymbalta Lawsuit. Updated November 4, 2022. Drugwatch. https://www.drugwatch.com/cymbalta/lawsuits/

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