‘No Reliable Evidence’ That Antidepressants Work for Chronic Pain

By Pat Anson, PNN Editor

Medical guidelines in the United States and United Kingdom may recommend antidepressants for treating chronic pain, but there is “no reliable evidence” that the medications actually work for that purpose, according to a new Cochrane review.

Cochrane reviews are considered the gold standard in medical research because they use robust methodology to gather good quality evidence, while dismissing poor quality research.

A team of UK researchers, led by scientists at the University of Southampton, spent two years examining 176 clinical trials involving nearly 30,000 patients who were prescribed antidepressants for pain. Among the drugs studied were fluoxetine (Prozac), sertraline (Zoloft), amitriptyline (Elavil), milnacipran (Savella), citalopram (Celexa), paroxetine (Paxil) and duloxetine (Cymbalta).

“Our review found no reliable evidence for the long-term efficacy of any antidepressant, and no reliable evidence for their safety for chronic pain at any point. Though we did find that duloxetine provided short-term pain relief for patients we studied, we remain concerned about its possible long-term harm due to the gaps in current evidence,” said lead author Tamar Pincus, PhD, a Psychology Professor at the University of Southampton.

“This is a global public health concern. Chronic pain is a problem for millions who are prescribed antidepressants without sufficient scientific proof they help, nor an understanding of the long-term impact on health.”

In the United States, duloxetine is FDA-approved for fibromyalgia, diabetic neuropathy and musculoskeletal pain. The recently updated CDC guideline recommends that duloxetine and other SNRI antidepressants be used for fibromyalgia and neuropathy, because they provide “small to moderate improvements in chronic pain and function.”

The UK’s National Institute for Health and Care Excellence (NICE) guideline goes even further, stating that antidepressants are better than opioids and other analgesics in treating fibromyalgia, chronic headache, Complex Regional Pain Syndrome (CRPS), musculoskeletal pain and other types of “primary chronic pain” for which there is no known cause.   

The authors of the Cochrane review say regulators in the US and UK should reconsider their recommendations.

“We are calling on governing health bodies NICE and the FDA to update their guidelines to reflect the new scientific evidence, and on funders to stop supporting small and flawed trials. Evidence synthesis is often complex and nuanced but the evidence underpinning the use of these treatments is not equivalent, so current treatment modalities are hard to justify,” said co-author Gavin Stewart, PhD, a statistician at Newcastle University.

Amitriptyline is one of the most commonly prescribed antidepressants for chronic pain in the world. In the last year, around 10 million prescriptions for amitriptyline were given to patients in England for pain, about twice the number prescribed for depression. Many other antidepressants are also prescribed “off-label” for pain, despite limited evidence to support their use.

“Though previous investigations show that some antidepressants might relieve pain, there has never been a comprehensive study examining all medications across all chronic conditions – until now,” said co-author Hollie Birkinshaw, PhD, a Research Associate at the University of Southampton.

“The only reliable evidence is for duloxetine. Adopting a person-centered approach is critical to treatment and, when patients and clinicians decide together to try antidepressants, they should start from the drug for which there is good evidence.”

The reviewers say duloxetine was the highest-rated antidepressant for treating fibromyalgia, musculoskeletal and neuropathic pain. Standard doses of duloxetine were just as effective as higher ones. Milnacipran was also effective at reducing pain, although the evidence was weaker.

“We simply cannot tell about other antidepressants because sufficiently good studies are not available – but it does not mean that people should stop taking prescribed medication without consulting their GP,” said Pincus.

A common complaint of patients who take duloxetine is that it makes them dizzy and nauseous. Many quickly become dependent on the drug and then have severe withdrawal symptoms when they stop taking it.

Several previous studies have also raised questions about using antidepressants for pain. A recent review of over two dozen clinical trials by Australian researchers found little evidence to support the use of antidepressants in pain management. Nearly half of the trials had ties or funding from the pharmaceutical industry.

Fibromyalgia Treatment Is a Real Gas

By Pat Anson, PNN Editor

Immersing fibromyalgia patients in high levels of oxygen is more effective at treating their pain and other symptoms than two medications commonly prescribed for the disorder, according to a new study.

Researchers at Tel Aviv University have been studying hyperbaric oxygen therapy (HBOT) for years as a possible treatment for fibromyalgia, a poorly understood condition characterized by widespread body pain, headaches, fatigue, depression and insomnia.  

Hyperbaric medicine is a form of treatment in which patients stay in a pressurized chamber and breathe 100% oxygen to help them heal faster. HBOT has long been used to treat infections, severe burns, carbon monoxide poisoning, and even scuba divers recovering from decompression sickness. The higher air pressure allows lungs to gather more oxygen than they would normally, and promotes the growth of new blood vessels and neurons in the brain.

In a 2015 study, researchers found that HBOT can also induce neuroplasticity in the brain and significantly reduce fibromyalgia pain.

"Until 15 to 20 years ago, there were doctors who believed that it was a psychosomatic illness and recommended that patients with chronic pain seek mental health care¸” said Shai Efrati, MD, of the Sagol Center for Hyperbaric Medicine and Research at Shamir Medical Center. “Today we know that it is a biological illness, which damages the brain's processing of the signals received from the body. When this processing is malfunctioning, you feel pain without any real damage in related locations.”

Efrati and his colleagues recruited 64 adults who suffer from fibromyalgia as a result of a traumatic head injury, and randomly assigned them to two groups.

One group was exposed to 100% pure oxygen in a hyperbaric chamber for 90 minutes, five times a week for three months; while the second group received either pregabalin (Lyrica) or duloxetine (Cymbalta), two FDA-approved medications for fibromyalgia.

The study findings, published in PLOS One, show that HBOT induced significant improvement in pain levels, quality of life, and emotional and social function. The clinical changes were correlated with increased brain activity in the frontal and parietal regions of the brain, which are associated with function and emotional processing.

A HYPERBARIC oxygen CHAMBER. 

"The results were dramatic," said Efrati. "At the end of the treatment, 2 out of 5 patients in the hyperbaric treatment group showed such a significant improvement that they no longer met the criteria for fibromyalgia. In the drug treatment group, this did not happen to any patient.

"In the group that received hyperbaric treatment, you could see the repair of the brain tissue, while in the control group there was only an attempt to relieve the pain -- without treating the damaged tissue -- and of course the medication group experienced the side effects associated with drug treatment.”

Duloxetine is an anti-depressant and pregabalin is an anti-seizure medication. Neither drug was initially developed to treat fibromyalgia, but were later repurposed as pain treatments.

"These drugs are not very effective,” said lead author Jacob Ablin, MD, from the Tel Aviv Sourasky Medical Center. "As a whole, existing treatments are not good enough. It is a chronic disease that significantly affects the quality of life, including young people, and hyperbaric medicine meets an acute need of these patients.”

Ablin says other non-pharmacological treatments are also beneficial for fibromyalgia, such as aerobic activity, hydrotherapy, cognitive-behavioral therapy and Tai Chi. He said quite a few patients request treatment with medical cannabis.

The studies are preliminary, and researchers say more long-term studies are needed to gauge the effects of HBOT after one, two and three years. But they’re encouraged by what they’re finding.

"This is a difference in approach: to cure instead of just treating the symptoms,” says Efrati. “Our goal as doctors is not only to treat the symptoms but to treat as much as possible the source of the problem, thus improving the quality of life of fibromyalgia patients."

Most Antidepressants Ineffective for Chronic Pain

By Pat Anson, PNN Editor

Most of the antidepressant drugs that are prescribed for chronic pain are either ineffective or the evidence supporting their use as pain relievers is weak, according to a new analysis published in The British Medical Journal (BMJ).

The use of antidepressants such as duloxetine (Cymbalta) and fluoxetine (Prozac) has doubled in recent years, with much of the increase due to their off-label prescribing to treat conditions such as fibromyalgia, neuropathy and back pain.

But in a review of 26 studies on the analgesic effects of antidepressants, Australian researchers found little evidence to support their use in pain management. The data on side effects was also weak, meaning the safety of antidepressants was also uncertain. Nearly half of the studies had ties or funding from the pharmaceutical industry.

“Recommending a list of antidepressants without careful consideration of the evidence for each of those antidepressants for different pain conditions may mislead clinicians and patients into thinking that all antidepressants have the same effectiveness for pain conditions. We showed that is not the case,” said lead author Giovanni Ferreira, PhD, from The Institute for Musculoskeletal Health at the University of Sydney.

“Some antidepressants were efficacious for some pain conditions; however, efficacy appears to depend on the condition and class of antidepressant. The findings suggest that a more nuanced approach is needed when prescribing antidepressants for pain.”

Ferreira and his colleagues say no study provided high quality evidence on the effectiveness of antidepressants for any pain condition. 

But they did find moderate quality evidence supporting the use of serotonin-norepinephrine reuptake inhibitors (SNRIs) for back pain, postoperative pain, fibromyalgia and neuropathic pain. Low-quality evidence suggested that SNRIs could be used for pain linked to breast cancer treatment, depression, knee osteoarthritis, and pain related to other underlying conditions.

The researchers say only low-quality evidence supports the use of selective serotonin reuptake inhibitors (SSRIs) for depression and pain related to other conditions; and tricyclic antidepressants (TCAs) as a treatment for irritable bowel syndrome, neuropathic pain, and chronic tension-type headaches. 

Antidepressants ‘Disappointing’ for Most Pain Patients

An accompanying editorial, also published in The BMJ, said the study adds to growing evidence that many medications prescribed for pain – not just antidepressants – are only modestly effective.

“Their findings suggest that for most adults living with chronic pain, antidepressant treatment will be disappointing. This is important given emerging concerns about increases in the prescribing of antidepressants and the challenges patients describe when trying to withdraw from treatment,” wrote Cathy Stannard, MD, UK National Health Service, and Colin Wilkinson, a pain patient and consultant at Centre for Pain Research, University of Bath.

“Clinicians continue to prescribe medicines for which the evidence is poor because they observe that some people respond to them, albeit modestly. But all medicines carry risk of harm and there are other, less potentially harmful options more likely to help people to live well with pain.”

Stannard and Wilkinson said exercise and physical activity might be better options than medication for some patients.

Ironically, a little over a year ago, the UK’s National Institute for Health and Care Excellence (NICE) released new guidelines that recommend antidepressants for adults with chronic primary pain, even when they are not depressed. NICE said antidepressants may help with quality of life, pain, sleep and psychological distress.

The NICE guideline is at odds with other studies that found antidepressants are minimally effective for back pain and osteoarthritis and often have adverse side effects. A common complaint of patients who take Cymbalta, for example, is how quickly they became dependent on the drug and have severe withdrawal symptoms when they stop taking it.

UK Guidelines Recommend Exercise and Antidepressants for Chronic Pain

By Pat Anson, PNN Editor

Doctors in the United Kingdom are being advised not to prescribe any type of painkiller to patients suffering from fibromyalgia, chronic headache, Complex Regional Pain Syndrome (CRPS), chronic musculoskeletal pain and other types of “primary chronic pain” for which there is no known cause.   

Those conditions should be treated with exercise, cognitive behavioral therapy (CBT), acupuncture and antidepressants, according to new guidelines released by the UK’s National Institute for Health and Care Excellence (NICE). The NICE guideline is far more strict on the use of analgesics than current treatment guidelines in the U.S. and Canada.

The recommendation against using painkillers goes beyond just opioids, and includes many widely used pain relievers such as paracetamol (acetaminophen), non-steroidal anti-inflammatory drugs (NSAIDs), gabapentinoids and corticosteroids, as well as benzodiazepines such as Valium and Xanax.

“There is little or no evidence that they make any difference to people’s quality of life, pain or psychological distress, but they can cause harm, including possible addiction,” NICE said in a statement.

The guideline says antidepressants such as duloxetine (Cymbalta) and fluoxetine (Prozac) “can be considered” for adults 18 and over with chronic primary pain, even when there is no diagnosis of depression. NICE said antidepressants may help with quality of life, pain, sleep and psychological distress.

“This guideline is very clear in highlighting that, based on the evidence, for most people it’s unlikely that any drug treatments for chronic primary pain, other than antidepressants, provide an adequate balance between any benefits they might provide and the risks associated with them,” Dr. Paul Chrisp, director of NICE’s Centre for Guidelines, said in a statement.

“People who are taking medicines to treat their chronic primary pain which aren’t recommended in the guideline should ask their doctor to review their prescribing as part of shared decision making. This could involve agreeing a plan to carry on taking their medicines if they provide benefit at a safe dose and few harms, or support for them to reduce and stop the medicine if possible.”

The NICE guideline sticks to more traditional recommendations for treating “chronic secondary pain” for which there is a known underlying cause, such as osteoarthritis, rheumatoid arthritis, ulcerative colitis and endometriosis. Pain management for palliative care is not covered in the guideline.

‘Patently Ridiculous’

Although a draft version of the NICE guideline was released last August, pain sufferers were startled by some of the final recommendations, especially those for acupuncture, CBT and exercise.

“The idea that a run around the block will zap the torment of people in chronic pain is patently ridiculous. It doesn’t do a damned thing for my hip,” said James Moore, a UK disability activist who uses a wheelchair. “Did none of the people who contributed to this not read it through this guidance and spot any of the gaping holes in its logic? How is it that I can see them and they can’t?”

“I fear the consequences for those with unsympathetic GPs who suddenly find themselves without medication that may work for them,” Moore wrote in the Independent. “This guidance urgently needs a rethink. Sadly, there may be torture looming for those in torment before we get one.”

The NICE guideline is at odds with recent studies that found antidepressants are minimally effective as pain relievers and often have adverse side effects. A common complaint of pain patients who take duloxetine, for example, is how quickly they became dependent on the drug and have severe withdrawal symptoms when they stop taking it.

The UK guideline also differs from treatment recommendations made by U.S. health agencies. The FDA and CDC recommend gabapentinoids for fibromyalgia, and acetaminophen and NSAIDs for low back pain and migraine.   

The CDC is currently in the process of updating and possibly expanding its opioid guideline to include recommendations for opioid tapering, short-term acute pain, migraine and other pain conditions. 

Antidepressants Ineffective for Back Pain and Osteoarthritis

By Pat Anson, PNN Editor

Antidepressants like duloxetine (Cymbalta) are increasingly being prescribed to treat various types of pain, but a new study shows the medications are largely ineffective for people suffering from chronic back pain or osteoarthritis and may even cause harm.

Many clinical guidelines recommend using antidepressants as pain relievers – even when depression is not involved -- yet evidence supporting that use is uncertain. To address that knowledge gap, researchers at the University of Sydney reviewed data from 33 controlled trials involving more than 5,000 adults who took antidepressants for low back or neck pain, sciatica, or hip or knee osteoarthritis.

Their findings, published in The BMJ, show that for people with back pain the effects of antidepressants were too small to be worthwhile, but for those with osteoarthritis there may be a small beneficial effect.

“The use of antidepressants to treat people with chronic back pain and osteoarthritis is increasing worldwide, but prior to our work, it was not clear whether antidepressants relieved pain or were safe,” said lead author Dr. Giovanni Ferreira, PhD, a postdoctoral research fellow at the Institute for Musculoskeletal Health at the University of Sydney. 

“We conducted a review of all randomised clinical trials evaluating the efficacy of antidepressants for people with back pain or knee osteoarthritis and found that for back pain the antidepressants were either ineffective or provided a very small effect, which was unlikely to be perceived as worthwhile by most patients. For people with osteoarthritis, effects were still small, but could be potentially perceived as worthwhile by some patients” 

Ferreira and his colleagues reviewed six classes of antidepressants: serotonin-noradrenaline reuptake inhibitors (SNRIs); selective serotonin reuptake inhibitors (SSRIs); noradrenaline-dopamine reuptake inhibitors (NDRIs); tricyclic antidepressants; and tetracyclic antidepressants. 

Results showed that SNRIs such as duloxetine reduced back pain after three months, but the benefits were so small they were unlikely to be considered clinically important to most patients. SNRIs had a slightly stronger effect on sciatica and osteoarthritis pain. 

Tricyclic antidepressants were ineffective for back pain, but might reduce pain in people with sciatica, although the evidence for that was weak.  

Industry Funded Studies 

Importantly, about two-thirds of people taking SNRI antidepressants experienced an adverse event such as nausea, fatigue, mood swings and weight gain.

“Many people are being treated with these medications that may not be helping their pain and may be doing them harm,” said Ferreira, adding that doctors need to be upfront with patients about possible side effects.

Researchers say the long-term effects of antidepressants prescribed for chronic pain are not well known and many of the studies that do exist were sponsored by industry, raising the risk of bias. 

“Many people are being treated with these medications that may not be helping their pain and may be doing them harm.”

— Dr. Giovanni Ferreira

“Large, definitive trials free of industry ties are urgently needed to evaluate the efficacy of antidepressants,” Ferreira said. “There needs to be more transparency about how evidence coming from those trials is appraised by guideline panels. A good starting point would be to consider all industry-funded trials to be at high risk of bias, and downgrade the strength of recommendations where industry-sponsored trials represent an important part of the available evidence.”

The Food and Drug Administration recently approved duloxetine as a treatment for fibromyalgia in pediatric patients, largely on the basis of a small trial conducted by Eli Lilly, Cymbalta’s manufacturer. Children enrolled in the study did show a modest improvement in pain, but several of them had serious adverse events, including two attempted suicides, suicidal thoughts, an intentional drug overdose, depression and hallucinations.

In their published findings in the journal Pediatric Rheumatology, Eli Lilly researchers downplayed the adverse events associated with duloxetine, saying they were not drug related or “not significantly different” than those of children on placebo. The two attempted suicides aren’t even mentioned.

A common complaint of patients who take duloxetine is how quickly they become dependent and what happens when they stop taking the drug. Many complain of severe withdrawal symptoms, including electric-like sensations called “brain zaps.”

Duloxetine’s checkered history is well known at the FDA. The agency’s adverse events reporting system has recorded nearly 35,000 cases involving duloxetine since 2007, most of them classified as psychiatric disorders. Over 4,000 of those adverse events resulted in death.

Study Finds ‘Evidence Lacking’ for Most Fibromyalgia Treatments

By Pat Anson, PNN Editor

A new analysis has found little evidence to support the long-term use of any medication or therapy to treat fibromyalgia, a poorly understood disorder characterized by widespread body pain, fatigue, poor sleep and depression.

An international team of researchers from Brazil and Australia reviewed 224 clinical trials of fibromyalgia treatments and found many of them small and of poor quality. High quality evidence was found for cognitive behavioral therapy (CBT), anti-depressants, and central nervous system (CNS) depressants as short and medium-term treatments for fibromyalgia. No treatment was found to be effective long term.

“In this systematic review, the effectiveness of most therapies for fibromyalgia was not supported. Strong evidence supported only cognitive behavioral therapy for pain, as well as antidepressants and central nervous system depressants for pain and quality of life, but these associations were small,” wrote lead author Vinícius Cunha Oliveira, PhD, an adjunct professor at Federal University of the Valleys of Jequitinhonha and Mucuri in Brazil.

“Some therapies may be associated with small reductions in pain and improvements in quality of life in people with fibromyalgia; however, current evidence is lacking for most therapies.”

The study findings, published in JAMA Internal Medicine, reflect what many fibromyalgia sufferers already know; many treatments are ineffective in improving their symptoms.

The Food and Drug Administration has approved only three drugs for fibromyalgia; the antidepressants duloxetine (Cymbalta) and milnacipran (Savella), and the anti-seizure medication pregabalin (Lyrica). All three drugs were originally developed for other medical conditions and are being repurposed as treatments for fibromyalgia.

A large 2014 survey of fibromyalgia patients by the National Pain Foundation found that most people who tried the three FDA-approved drugs did not feel they were effective.

Exercise, acupuncture, massage, electrotherapy, myofascial release, and several other non-pharmaceutical treatments are also commonly recommended for fibromyalgia pain. Researchers found only “moderate” evidence to support their short-term use. High quality evidence was only found for CBT, a form of meditation in which a therapist works with a patient to reduce unhelpful thinking and behavior.

“Clinicians should be aware that current evidence for most of the available therapies for the management of fibromyalgia is limited to small trials of low methodological quality,” researchers concluded. “Clinicians and patients should choose therapies by considering other important outcomes in addition to those presented in this review, such as adverse effects, out-of-pocket costs, and patient preferences.”

The National Institutes of Health estimates about 5 million Americans have fibromyalgia. Most people diagnosed with fibromyalgia are women, although men and children also can be affected.

Study Finds Most Drugs Ineffective for Neuropathic Pain

By Pat Anson, PNN Editor

A first of its kind study that compared four medications widely used to treat neuropathy found that all four were usually ineffective in treating pain and many patients stopped taking them due to side effects.    

Over 20 million people in the U.S. suffer from neuropathic pain, a tingling, burning or stinging sensation in the hands and feet caused by nerve damage. Neuropathy is often caused by diabetes, chemotherapy or trauma, but in about 25% of cases the cause is unknown and classified as cryptogenic sensory polyneuropathy (CSPN).

There is little guidance for physicians and patients on what drugs to take for CSPN, so researchers at the University of Missouri School of Medicine conducted a “real world” study in which 402 patients with CSPN took one of the four neuropathy medications.

The four drugs studied were nortriptyline (Aventyl), a tricyclic antidepressant; duloxetine (Cymbalta), a serotonin-norepinephrine reuptake inhibitor (SNRI) antidepressant; pregabalin (Lyrica), an anti-seizure drug; and mexiletine (Mexitil), an anti-arrhythmic medication used to treat irregular heartbeats.

Nortriptyline, duloxetine and pregabalin are approved by the FDA for treating neuropathy, while mexiletine is used off-label. None of the drugs were originally developed to treat neuropathic pain.

"As the first study of its kind, we compared these four drugs in a real-life setting to provide physicians with a body of evidence to support the effective management of peripheral neuropathy and to support the need for newer and more effective drugs for neuropathic pain," said lead researcher Richard Barohn, MD, executive vice chancellor for health affairs at the University of Missouri.

After 12 weeks of use, any drug that reduced pain for a patient by at least a 50% was considered effective, a recognized industry standard to define therapy success.. Researchers also kept track of patients who stopped taking a drug and dropped out of the study due to adverse effects.

The study findings, published in JAMA Neurology, can best be described as underwhelming. Patients were far more likely to stop taking a drug than they were to stay on a medication that was helping them.    

Of the four drugs, only nortriptyline was an effective pain reliever for at least 25% of patients. It also had the second-lowest drop-out rate (38%), giving it the highest level of overall utility. Duloxetine had the second-highest efficacy rate (23%) and the lowest drop-out rate (37%).

Pregbalin had the lowest efficacy rate (15%) and the second highest drop-out rate (42%), while mexiletine had the highest drop-out rate (58%) and an efficacy rate of 20 percent.

EFFICACY RATE OF NEUROPATHY DRUGS

SOURCE: JAMA NEUROLOGY

"There was no clearly superior performing drug in the study," Barohn said. "However, of the four medications, nortriptyline and duloxetine performed better when efficacy and dropouts were both considered. Therefore, we recommend that either nortriptyline or duloxetine be considered before the other medications we tested."

While nortriptyline had the highest efficacy rate, it also had the highest rate of adverse events, with over half of patients (56%) reporting side effects such as dry mouth, drowsiness, fatigue and bloating.  

Previous studies have found that duloxetine and pregabalin had higher efficacy rates for neuropathic pain, but Barohn and his colleagues say their research more accurately reflects what patients experience in real life and what physicians encounter in their practice.

“Our findings could affect how these 4 drugs are used by all physicians who treat patients with neuropathy. Findings support duloxetine and nortriptyline as better-performing drug choices in this population with neuropathic pain, suggesting that they should be prescribed before pregabalin or mexiletine are considered. However, this study also supports a finding that all 4 drugs helped improve pain in at least some patients, so each could be tried if others failed,” they concluded.     

There are several other drugs used to treat neuropathy, including gabapentin, venlafaxine and sodium channel inhibitors. Barohn says additional comparative studies should be performed on those drugs. His goal is to build effectiveness data on nearly a dozen drugs for CSPN.

Should Children Be Prescribed Cymbalta?

By Pat Anson, PNN Editor

The Food and Drug Administration has quietly expanded the use of an antidepressant to treat fibromyalgia in pediatric patients between 13 to 17 years of age – despite the known risk of suicidal behavior by children on antidepressant drugs.  

Cymbalta (also known by its generic name, duloxetine) is a serotonin and norepinephrine reuptake inhibitor (SNRI) made by Eli Lilly that was first approved by the FDA as a treatment for depression in 2004.

In the years that followed, Cymbalta’s use greatly expanded as it was also approved as a treatment for anxiety, diabetic neuropathy, chronic musculoskeletal pain and fibromyalgia in adults.

The approvals came with a major caveat: a black box warning label that specifically cautioned patients and providers that “Cymbalta is not approved for use in pediatric patients” because it could increase the risk of suicidal thinking and behavior in children.

2007 Cymbalta warning label

So why is the FDA now approving the use of Cymbalta by children?  

The federal agency issued no press release when it sent a letter to Eli Lilly on April 20 notifying the company that it was approving its longstanding request to allow Cymbalta to be prescribed for juvenile fibromyalgia. Lilly itself has made no public announcement about the approval.

Health and Human Services Secretary Alex Azar, who oversees the FDA, was President of the U.S. division of Eli Lilly from 2012 to 2017, a period when the cost of Cymbalta doubled.

‘No New Safety Concerns’

The FDA’s approval of Cymbalta for pediatric cases appears to be based on a single placebo-controlled study -- sponsored by Eli Lilly -- in which 184 children with juvenile fibromyalgia were given duloxetine, placebo or a combination of the two over the course of 39 weeks.

Eli Lilly not only funded the study, but its employees designed it, collected data, conducted the analysis, and wrote the article that reported on its findings, which was published last year in the journal of Pediatric Rheumatology.

While the study did not show that duloxetine was significantly better than placebo, patients taking the drug did show a modest improvement in pain severity. Notably, Eli Lilly researchers also said they found “no new safety concerns” about duloxetine.

Which doesn’t mean there were no safety concerns, it just means they didn’t find any new ones. Duloxetine is well known to have side effects in adults, such as fatigue, nausea, mood swings and weight gain.

“The safety profile of duloxetine observed in this study was similar to that observed in previous pediatric duloxetine trials of other indications, as well as in duloxetine trials in adults with FM (fibromyalgia). Nausea, headache, vomiting, and decreased appetite were the most frequently reported AEs (adverse events) in the present study, which are similar to those reported previously in adult population with FM,” wrote lead author Himanshu Upadhyaya, Global Lead Physician in Psychiatry at Eli Lilly.

But a closer look at the study findings – which anyone can see for themselves at clinicaltrials.gov – shows that 6 children taking duloxetine exhibited alarming signs of self-harm. There were two attempted suicides and one intentional drug overdose. One child intentionally injured himself and two had suicidal thoughts. Three other children on duloxetine experienced depression, hallucinations and a seizure.

Granted, nine children in total isn’t that many – but in a small study with 184 participants, it’s concerning – especially when no one in the placebo group had the same behavior or symptoms, according to study results posted on the government-run website.

However, in their published findings in Pediatric Rheumatology, Eli Lilly researchers downplayed the suicidal thinking and other side effects associated with duloxetine, saying they were “not significantly different” than those of children on placebo. The two attempted suicides aren’t even mentioned.

“In the present study, the suicidal ideation events reported with duloxetine were not significantly different from placebo-treated patients. Similar results were reported previously, including the exposure-adjusted analysis of suicidal ideation events, which have not shown any significant difference between duloxetine and placebo,” researchers said.

“None of the SAEs (serious adverse events) reported were considered to be study drug-related and none have led to study discontinuation. There were no deaths reported during the study. There were no significant differences between groups in suicide-related behaviors or ideation.”

Eli Lilly went to great lengths to conduct the study. Its researchers said it took almost 7 years and significant recruitment efforts to find enough children to participate with parental approval. Most of the participants were in the United States, but some were recruited as far away as India and Argentina.

Suicide has long been associated with duloxetine, going back to its earliest clinical trials. A 19-year college student participating in one study killed herself in 2004, four days after being taken off the drug. Four other patients who took duloxetine during clinical trials also committed suicide, although Eli Lilly said at the time there was no evidence directly linking those deaths to the drug.

Withdrawal ‘Brain Zaps’

A common complaint of patients who take duloxetine is how quickly they become addicted and what happens when they stop taking the drug. Many complain of severe withdrawal symptoms such as mood swings, nausea, fatigue and electric-like sensations called “brain zaps.”

PNN columnist Crystal Lindell went through withdrawal when she started weaning herself off Cymbalta in 2015. Her column on that experience (see “How I took Myself Off Cymbalta”) has become a reference point for hundreds of patients trying to get off the drug.

Crystal thinks expanding the use of Cymbalta to include pediatric patients is not a good idea.

“I would urge extraordinary caution when it comes to giving Cymbalta to teenagers,” Crystal says. “When I was first given Cymbalta about seven years ago, I was 29. At that time, the doctor told me I may be too young to take it because it was known to cause suicidal thoughts in young people. He advised me to be in touch with him if that starts to happen. And I was much older than the age group they just approved to take this drug.  

“I hope doctors will be more cautious about giving Cymbalta to teenagers than they have been about giving it to adults. I always advise readers to listen to their doctor first and foremost, but don't be shy about pressing them on which medications they prescribe you. Ask them about side effects and withdrawal so that you can feel comfortable about what you’re taking.”

The FDA’s new warning label for Cymbalta still cautions about suicidal thinking and behavior in children, but no longer warns that the drug is not approved for use by pediatric patients.

NEW CYMBALTA WARNING LABEL

Duloxetine’s checkered history is well known at the FDA. The agency’s adverse events reporting system has recorded over 33,500 serious cases involving duloxetine since 2007, most of them classified as psychiatric disorders. Over 3,900 of those adverse events resulted in death.

Although Eli Lilly’s patent on duloxetine expired years ago, Cymbalta remains a top money-maker for the company. Cymbalta sales during the first quarter of 2020 were up 28% from a year ago to more than $210 million.

In addition to treating juvenile fibromyalgia, Cymbalta could be repurposed in other ways to boost sales for Eli Lilly. Over 300 clinical studies are underway to explore the use of duloxetine to treat a smorgasbord of other conditions, including shingles pain, cancer pain, surgical pain, post-traumatic stress disorder, attention deficit disorder, and cocaine addiction.

In short, a drug with risky side effects that was originally developed to treat depression is being used for health conditions it was never intended to treat. And more could be added to the list.

Lyrica, Cymbalta and Savella: Do They Work?

By Lana Barhum, Columnist

If you have fibromyalgia, chances are your doctor has prescribed one or more of the three drugs approved for fibromyalgia by the U.S. Food and Drug Administration (FDA).   It is also likely you have been disappointed when they didn’t work and by the side effects they caused.

I have tried Lyrica (pregabalin), Cymbalta (duloxetine) and Savella (milnacipran). My experience is they don’t work well and clinical research doesn’t offer up enough credible evidence that they do.

Patient feedback on these medications is actually more telling than recent studies.  Just check any fibromyalgia online forum and you will find your unpleasant experiences with these medications aren’t unique and shared by many.

Lyrica

Lyrica was developed by Pfizer as a treatment for epilepsy, but it is now widely prescribed for many different types of pain. Lyrica was approved by the FDA in 2007 as the first drug specifically for the treatment of fibromyalgia. Pfizer notes on its website that Lyrica “significantly relieves fibromyalgia pain and improves physical function” in fibromyalgia patients.  But does it really?

An initial study from 2005, with results published in Arthritis & Rheumatology, found Lyrica to be effective at relieving pain in only 29% of the 529 fibromyalgia patients in the study group. 

A major shortcoming of the study was that weight gain affected 10% of the study participants.

What was also interesting about the Arthritis & Rheumatology study is that a large number of participants dropped out due to Lyrica's side effects, which included edema, dry mouth, weight gain, infection, increased appetite and constipation.

A 2014 study of out of the University of Calgary, with results published in the journal Therapeutic Advances in Drug Safety,  also found that Lyrica causes edema and weight gain in some patients. 

Those side effects, especially the weight gain, aren’t worth it for a drug that doesn’t seem to work well for most people. You would get more benefit from dietary changes for fibromyalgia than with Lyrica - at least that was my experience. 

All I got from taking Lyrica was a 40 pound weight gain that took me two years to take off. I made the mistake of staying on it for too long, believing that it would one day work for me.

Cymbalta

Cymbalta was originally developed and marketed by Eli Lilly as a treatment for depression. You may even remember some of the commercials for it. In 2008, Cymbalta become the second drug approved by the FDA to treat fibromyalgia.

While Cymbalta doesn’t have stellar ratings amongst fibromyalgia patients, it does outperform Lyrica in my opinion. Initial trials, with results published in The Primary Care Companion to The Journal of Clinical Psychiatry, show that over a third (36%) of study participants reported at least a 50% reduction in pain, based on a dosage of 60 mg once or twice per day.

A report published in the journal Expert Review of Clinical Immunology found that many participants dropped out of Phase I, II, and III trials of Cymbalta due to side effects, including nausea, headache, and sleep issues. 

Cymbalta has given me some pain relief over the years, but I have also made changes to my diet and lifestyle which may have helped as well.  If Cymbalta has helped me with anything, it is managing the depressed feelings fibromyalgia often leaves in its wake.

Savella

My Savella experience was far worse than my experiences with Lyrica and Cymbalta.  I could only stay on it for two weeks because the side effects were more than I could handle. Dizziness, vertigo, nausea, fatigue, and severe headache were a few of the side effects that stood out.  And I didn’t get any fibromyalgia pain or symptom relief.

Savella was developed by Forest Laboratories specifically for fibromyalgia and was approved by the FDA in 2009.

Like Lyrica and Cymbalta, studies confirm Savella’s poor performance. One double-blind study, reported in the journal Pharmacy & Therapeutics, found that only about one in four fibromyalgia patients (26%) were getting pain relief. 

The rate of discontinuation due to Savella’s side effects and treatment failure was also high -- nearly 43 percent.

In 2010, the consumer advocacy group Public Citizen petitioned the FDA to remove Savella from the market because it increased blood pressure in patients who didn’t have high blood pressure to start with. The group also argued Savella posed an increased risk for suicidal thoughts.

The FDA responded last year and denied Public Citizen’s petition, but said it would continue to monitor the safety of Savella.

My Thoughts

The only medication that I have seen that offers real improvement is Pfizer’s Neurontin (gabapentin), which is prescribed “off label” because it is not specifically approved to treat fibromyalgia by the FDA. Neurontin has helped my nerve pain and I also take muscle relaxers as needed, as I am frequent sufferer of muscle cramps and spasms. 

Studies have confirmed Neurontin’s effectiveness in treating fibromyalgia pain and improving sleep and fatigue. One double-blind study, with results published in Arthritis & Rheumatism, found that over half (51%) of fibromyalgia patients were finding relief with Neurontin.   

That’s not bad for a medication that was originally developed to manage seizures and whose formula has been the same since 1993. While it has helped me, I certainly understand Neurontin hasn’t helped everyone. There are even reports of Neurontin being abused by addicts. 

I am not sure why the makers of Lyrica, Cymbalta and Savella continue to market medications that don’t offer most people real results.  Yet, these medications remain available and doctors are still prescribing them to treat fibromyalgia. 

Let's just hope there are new fibromyalgia drugs on the horizon that actually work and give us real and reliable symptom and pain relief.

What has been your experience with Lyrica, Cymbalta and Savella?

Lana Barhum is a freelance medical writer, patient advocate, legal assistant and mother. Having lived with rheumatoid arthritis and fibromyalgia since 2008, Lana uses her experiences to share expert advice on living successfully with chronic illness. She has written for several online health communities, including Alliance Health, Upwell, Mango Health, and The Mighty.

To learn more about Lana, visit her website.

The information in this column should not be considered as professional medical advice, diagnosis or treatment. It is for informational purposes only and represent the author’s opinions alone. It does not inherently express or reflect the views, opinions and/or positions of Pain News Network.

Two Drug Combo More Effective for Fibromylagia

By Pat Anson, Editor

Two drugs commonly prescribed for fibromyalgia – Lyrica and Cymbalta – are more effective in treating the disorder when used together, according to a new study by Canadian researchers.

Lyrica (pregabalin) is an anti-seizure nerve drug, while Cymbalta (duloxetine) works primarily as an anti-depressant. Both have been used for years to treat fibromyalgia -- a poorly understood disorder characterized by deep tissue pain, fatigue, insomnia, and mood swings. Until now no one has studied how effective the two drugs could be when used in combination.

"We are very excited to present the first evidence demonstrating superiority of a duloxetine-pregabalin combination over either drug alone," said lead author Ian Gilron, MD, Director of Clinical Pain Research at Queen’s University in Kingston, Ontario.

“The results of this trial suggest that combining pregabalin with duloxetine can safely improve outcomes in fibromyalgia including pain relief, physical function and overall quality of life.”

This was a small study – only 41 fibromyalgia patients participated – and the researchers admit that larger trials are needed to see if the results can be replicated. The new research was published in the journal Pain.

The study is the latest in a series of clinical trials -- funded by the Canadian Institutes of Health Research -- which Gilron and his colleagues have conducted on combination therapies for chronic pain conditions. By studying promising drug combinations, they hope to show physicians how to make the best use of current treatments.

"The value of such combination approaches is they typically involve drugs that have been extensively studied and are well known to health-care providers," says Gilron.

Patients in the study were divided into three groups that either took pregabalin alone, duloxetine alone or a combination of the two for six weeks. Doses were gradually increased in the study to the maximum tolerated dose. When used in combination, patients could only tolerate relatively low doses of pregabalin and duloxetine, suggesting the drugs have an overlap effect when used together.

“The pharmacological diversity of a pregabalin-duloxetine combination is a mechanistically appealing feature that increases the likelihood of additive analgesic actions although there could similarly be some additive adverse effects with this combination. Even at significantly lower doses during combination therapy, superior global pain relief during combination therapy would suggest a greater additive effect for pain reduction than for side effects,” said Gilron.

The biggest side effect of the pregabalin-duloxetine combination was drowsiness, and the researchers admit that reduced physical activity caused by drowsiness could have contributed to pain reduction. 

Patients have long complained of other side effects from pregabalin and duloxetine when used separately, such as weight gain, nervousness, and brain fogginess. Many have also reported severe withdrawal symptoms and “brain zaps” when trying to get off the drugs. The study apparently didn’t address those issues. 

Lyrica (pregabalin) is one of Pfizer’s top selling drugs and generates over $5 billion in revenue annually. In addition to fibromyalgia, Lyrica is approved by the Food and Drug Administration to treat chronic pain associated with epilepsy, shingles, diabetic peripheral neuropathy, and spinal cord injury. The drug is also prescribed “off label” to treat lumbar spinal stenosis, the most common type of lower back pain in older adults.

Cymbalta (duloxetine) generated sales of $5 billion for Eli Lilly until its patent expired in 2013 and cheaper generic versions of duloxetine became available. Cymbalta is approved for fibromyalgia, neuropathy, osteoarthritis, depression and anxiety.

Only one other medication – Savella – is approved by the FDA for fibromyalgia, but it is not as widely used as the other drugs.

Fibromyalgia was initially thought to be a musculoskeletal disorder, but research now suggests it's a disorder of the central nervous system - the brain and spinal cord. Researchers believe that fibromyalgia amplifies painful sensations by affecting the level and activity of brain chemicals responsible for processing pain signals. It affects twice as many women as men.