In 2007, Pfizer’s Lyrica became the first prescription medication approved for the treatment of fibromyalgia. Since then, two more drugs—Cymbalta and Savella—have joined its ranks, expanding the options to treat this painful chronic condition.
Cymbalta is an antidepressant that may help control fibromyalgia pain and fatigue.
But because so much is still unknown about what causes fibromyalgia, there is no go-to treatment. In fact, typically only “35% to 40% of patients will respond well to any one of these three drugs,” says Daniel Clauw, MD, the director of the Chronic Pain and Fatigue Research Center at the University of Michigan, in Ann Arbor.
Research suggests that people with fibromyalgia may have extremely sensitive central nervous systems that perceive pain much more acutely than those with normal pain responses. There is also some evidence that people who suffer from fibromyalgia experience a range of sleep disturbances that may leave them more prone to pain. An even newer theory is that fibromyalgia may be related to compression of the cervical spinal cord, which can lead to sleep disruptions as well as widespread pain.
The three drugs currently approved for fibromyalgia are thought to ease the pain by acting on either the nerves or brain chemicals called neurotransmitters. Since these drugs do not have a high success rate, patients often use more than one or try several before finding one that works well with the least side effects.
“People should be encouraged to find someone who is willing to work with them to find that combination or single treatment that works well,” says Charles E. Argoff, MD, a professor of neurology at Albany Medical College in New York.
You may find that over-the-counter medications help to alleviate some of the pain flare-ups associated with fibromyalgia. But if you’ve been diagnosed with the condition and are looking for long-term treatment, talk to a doctor about prescription drugs. Here’s a brief breakdown of different medications used to treat fibro pain, both on- and off-label.
Lyrica
How it works: The first drug approved to treat fibromyalgia, Lyrica (pregabalin) is an anticonvulsant that the U.S. Food and Drug Administration (FDA) previously approved in late 2004 to treat pain associated with diabetic neuropathy and shingles. The medicine is believed to calm overactive neurons as well as possibly influence the release of neurotransmitters.
Recommended dosage: Begin at 150 mg daily, and can be increased to a maximum of 450 mg per day
When it may be prescribed: “Most of us think that if people have a prominent sleep disturbance, we should use Lyrica or Neurontin first,” says Dr. Clauw. Neurontin (gabapentin) is an anticonvulsant that has not been approved for, but is often used to treat, fibromyalgia.
What to consider: The most common side effects are dizziness, weight gain, fatigue, difficulty concentrating, and swelling in the hands and feet. In April 2009, the FDA also began requiring Lyrica to carry a warning that the drug increases the increase the risk of suicidal thoughts or behavior.
Cymbalta
How it works: Approved in 2008 for use in fibromyalgia (and previously approved for diabetic retinopathy and depression), Cymbalta (duloxetine) is a serotonin and norepinephrine reuptake inhibitor (SNRI)—a type of antidepressant that raises the levels of the neurotransmitters serotonin and norepinephrine in the brain and body. These highly sensitive brain chemicals seem to play a role in the perception of pain and keeping them at consistent levels appears to help alleviate it.
Recommended dosage: 60 mg once a day
When it may be prescribed: Since depression often accompanies fibromyalgia, experts say that SNRIs such as Cymbalta may be a good choice for someone who experiences depression or fatigue in conjunction with his or her pain.
What to consider: Common side effects of SNRIs include nausea, vomiting, dry mouth, constipation, loss of appetite, and dizziness, but those side effects may improve over time. All SNRIs can cause or exasperate hypertension, so patients should have their blood pressure checked regularly.
A more significant concern is the interaction these drugs can have with other medications that affect serotonin, especially migraine medications and the painkiller tramadol. Since 70% of people with fibromyalgia are on more than one medication, drug interactions are an important consideration, says Andrew J Holman MD, clinical rheumatologist and associate clinical professor of medicine at the University of Washington. Like all antidepressants, Cymbalta is required to carry a black box warning about an increased risk of suicidal thinking and behavior in people under the age of 25.
Savella
How it works: Approved in January 2009, Savella (milnacipran) is also an SNRI.
Recommended dosage: 100 mg daily, begun at a much lower dosage and increased over a week
When it may be prescribed: Like Cymbalta, clinicians may choose Savella when someone with fibromyalgia also suffers from depression or has significant fatigue.
What to consider: The side effects of Savella are similar to those of Cymbalta. Savella also carries a warning about the risk of cardiovascular side effects, most notably hypertension, increased heart rate, and heart palpitations. Patients taking the drug should have their blood pressure monitored periodically. Like all antidepressants, Savella is required to carry a black box warning about an increased risk of suicidal thinking and behavior in people under the age of 25.
Off-label: Other antidepressants
Doctors often prescribe drugs off-label to treat medical conditions; this means they prescribe a drug to treat a condition for which it has not been approved by the FDA but has shown promise in practice. For fibromyalgia, the most common medications prescribed off-label are tricyclic antidepressants such as amitriptyline, or a chemically similar muscle relaxant, cyclobenzaprine (Flexeril).
How it works: Tricyclic antidepressants (TCAs) were among the first antidepressants developed. Like SNRIs, they control the level of serotonin and norepinephrine in the brain, but also affect the neurotransmitter dopamine.
Recommended dosage: Because they are not approved for fibromyalgia, doctors must work with a patient to figure out the right dosage; some may not be willing to prescribe the drugs off-label.
When it may be prescribed: Because they have been around for so long and are available as generics, TCAs are often the cheapest medication option and can be used when cost is a concern. In addition, says Dr. Clauw, TCAs have been shown to alleviate other symptoms of fibromyalgia besides joint and muscle pain, such as interstitial cystitis (which causes pain the in bladder) and irritable bowel syndrome. One of the side effects of TCAs, drowsiness, means it may be a good choice for people who have trouble falling asleep, says Dr. Clauw. (Savella and Cymbalta can be stimulating.)
What to consider: Because TCAs affect so many receptors in the brain, more people experience side effects—such as dry mouth and fatigue—than with the other medications. All TCAs carry a black box warning about an increased risk of suicidal thinking and behavior in people under the age of 25.
Selective serotonin reuptake inhibitors (SSRIs), another kind of antidepressant, are also sometimes used to treat fibromyalgia, either alone or in combination with a TCA. These medications include fluoxetine (Prozac) and sertraline (Zoloft) and are prescribed when symptoms include severe mood problems. Atypical antidepressants such as bupropion (Wellbutrin) may also be prescribed off-label.
What’s next
In early 2009, a Stanford University study found that low doses of the drug naltrexone helped reduce pain and fatigue in women with fibromyalgia. Naltrexone is relatively inexpensive and has been used for years to treat drug addiction, but it has only been used off-label to ease fibromyalgia symptoms. Researchers say the study was too small for them to make any new recommendations, but that the results were promising.
The importance of other therapies
Since medication is not universally successful and because the causes of fibromyalgia are so poorly understood, Dr. Argoff cautions that “medication alone is not the solution” and recommends that it be combined with lifestyle changes such as good sleep hygiene and moderate aerobic exercise as well as complementary therapies, such as cognitive behavioral training, to manage pain.
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