Some patients who suffer withdrawal symptoms when trying to discontinue the antidepressant Cymbalta report those symptoms are far worse than what they were led to expect.

Cymbalta is the brand name for duloxetine hydrochloride, a pharmaceutical product of Eli Lilly & Co. It is one of a class of psychiatric medications known as selective serotonin reuptake inhibitors, or SSNRIs.

Today, Cymbalta is approved as a treatment for major depressive disorder, generalized anxiety disorder, diabetic peripheral neuropathy, fibromyalgia, and chronic musculoskeletal pain.

Cymbalta was first approved by the FDA in August 2004. As it was a new addition in a market hungry for antidepressants, sales were brisk. Cymbalta sales were up to $5 billion per year before its patent expired, allowing generic versions to enter the market.

However, Cymbalta has developed a reputation as being difficult to discontinue due to the onset of Cymbalta withdrawal symptoms. Probably the most dramatic of these are what have come to be known as “brain zaps” – sensations of electric shock inside the head.

Other symptoms of Cymbalta withdrawal include mood swings, dizziness, nausea and vomiting, tunnel vision, and headache severe enough to inhibit normal daily work functions. The FDA’s warning label also lists diarrhea, paresthesia, irritability, insomnia, anxiety, hyperhidrosis and fatigue. Some patients have also reported suicidal thoughts, body shaking, and changes in weight.

Some of those who quit Cymbalta reported these withdrawal symptoms continued for weeks, or sometimes months, after they took their last dose.

Some Cymbalta patients have established support group websites to share their stories of the difficulty of Cymbalta withdrawal. One patient described being forced to quit Cymbalta cold-turkey due to a change in insurance that raised her cost for Cymbalta beyond what she could pay. She described her ensuing brain zaps as being worse than having broken ribs. She also reported starting fights with her family members for no apparent reason during her Cymbalta withdrawal.

Cymbalta Lawsuits

Plaintiffs in Cymbalta lawsuits argue that Lilly does not properly warn them or their physicians about the serious risk of Cymbalta withdrawal. In a 2012 review of 48 reports to the FDA of serious cases of Cymbalta withdrawal, the non-profit reporting service Quarter Watch found inconsistencies between the severity of symptoms in the reports and the information provided to consumers in Cymbalta’s warning materials.

Some plaintiffs have pointed out what they believe are inadequacies in the FDA’s approved labeling for Cymbalta, claiming the label understates the true risks. The FDA’s current labeling lists certain symptoms that it says were reported at a rate of only “1% or greater,” but plaintiffs have presented evidence from clinical trials that withdrawal symptoms occurred in trial subjects at rates as high as 45 percent.

The label lists other symptoms, including “paresthesias such as electric shock sensations,” as being associated with “other SSRIs and SNRIs.” But it implies these symptoms may be only potentially associated with Cymbalta.

The label also suggests the patient consider resuming the original dose of Cymbalta if intolerable symptoms occur, effectively abandoning the attempt at discontinuation. In fact, the inability to quit Cymbalta due to intolerable withdrawal symptoms is one of the problems some patients face.