Eli Lilly & Co. is facing dozens of lawsuits from people who experienced withdrawal symptoms after stopping Cymbalta (duloxetine). The label states that withdrawal occurs in at least 1% of patients, but studies have found that at least 50% of patients experience withdrawal and 10% of cases are severe.
Cymbalta and Withdrawal
Cymbalta (duloxetine) is an antidepressant medication manufactured by Eli Lilly & Co. that has been on the market since 2004. The link between antidepressants and withdrawal has been known since at least as early as 2001. Severe withdrawal is reported in patients discontinuing many psychiatric medications, such as antidepressants, benzodiazepines, amphetamines, and opioids.
Studies Link Cymbalta and Severe Withdrawal
Before Cymbalta was approved, the FDA required a clinical trial to investigate withdrawal from Cymbalta. The patients took Cymbalta for 8-9 weeks, were abruptly switched to a placebo, and monitored for an additional 1-2 weeks.
During the monitoring period, researchers found that 40-50% of patients reported withdrawal symptoms. In 10% of patients, the symptoms were severe. More severe withdrawal was reported by patients on higher doses (up to 120-mg/day).
The most common side effects included dizziness (12.4%), nausea (5.9%), headache (5.3%), paresthesia that might include “brain zaps” (2.9%), vomiting (2.4%), irritability (2.4%), and nightmares (2.0%).
Results of this study were published in January 2005 by the Journal of Affective Disorders.
What is the problem?
- Studies may underestimate severe withdrawal from Cymbalta: The trial lasted only two months, but many people take Cymbalta for many years.
- No one knows how long symptoms may last: The monitoring period was only 1-2 weeks. At the end, 54% of patients still had symptoms of withdrawal. Researchers did not follow up to see if symptoms resolved or persisted.
- Warning labels may be inadequate: Lawsuits have been filed by people who were forced to continue taking Cymbalta because withdrawal symptoms were so severe.
Warning Label for Cymbalta Withdrawal Symptoms
Eli Lilly & Co. has tried to dismiss a class action and dozens of lawsuits from people who accuse the drug-maker of failing to warn about withdrawal. Eli Lilly claims that the warning label is adequate.
The label states that withdrawal “occurred at a rate greater than or equal to 1%.” Although this is technically true, the actual figure is at least 50% and may be even higher for people who took high doses for many years.
The Prescribing Information states:
“Never stop an antidepressant medicine without first talking to a healthcare provider. Stopping an antidepressant medicine suddenly can cause other symptoms.”
This label has been called “materially deficient” because it does not state how often “other symptoms” occur, how severe the symptoms might be, or what patients can do to reduce the risk (such as gradually tapering the dosage). In fact, the information warns against breaking or opening the capsule, which is necessary for tapering the dosage.
What is a Brain Zap?
The “brain zap” has been reported by many people in withdrawal from Cymbalta. It has been described as an “electric-like” sensation that occurs suddenly, only lasts a few seconds, and may recur several times before going away. It typically feels like pin-pricks, zapping, fizzing, or pounding inside the skull. Dizziness is also commonly reported. Some experts believe it is a form of paresthesia, which was reported by about 3% of patients in clinical trials.
Symptoms of Withdrawal from Cymbalta
- Brain zaps
- Paresthesia (tingling, burning, itching, etc.)
- Psychiatric problems
- Suicidal ideation
- Personality changes
- Changes in appetite or weight gain
- And more