The Use of Cymbalta in Fibromyalgia Treatment

Cymbalta (duloxetine) is FDA-approved for fibromyalgia, depression, diabetic neuropathy, and chronic musculoskeletal pain.

Its 2008 approval made it just the second drug approved for treating fibromyalgia. A generic form is available in the U.S.

Cymbalta and the other approved drugs, Lyrica (pregabalin) and Savella (milnacipran), are considered first-line treatments for fibromyalgia. That means they're recommended before any other drugs. They work well for some but not for everyone. For some people, they cause side effects that are either dangerous or unpleasant enough to make people go off of them. For others, they just don't work very well.

(This isn't unique to Cymbalta. No single treatment helps all of us with this illness.)

What Cymbalta Does

Cymbalta is classified as an SNRI or serotonin-norepinephrine reuptake inhibitor. What does that mean?

Serotonin and norepinephrine are neurotransmitters (chemical messengers in your brain.) Serotonin is involved in the sleep-wake cycle and pain processing. Norepinephrine helps you feel alert and interested as well as playing a role in memory.

Both of these neurotransmitters are believed to be dysregulated in fibromyalgia, meaning that we either don't have enough or what we have isn't used efficiently by our brains. Either way, we could use more of them.

Cymbalta and other SNRIs don't add serotonin and norepinephrine to our brains, but they make it available for longer, which basically has the same effect as adding more. To do that, they slow down a process called reuptake in which specialized cells in your brain clear away used serotonin and norepinephrine after it's been used to send messages from one neuron to another. (It's like the neurotransmitter is an envelope left lying around after you open your mail.) Keeping the neurotransmitter around longer lets your brain use it more efficiently.

Cymbalta for Reducing Fibromyalgia Pain

Multiple clinical trials show that Cymbalta can reduce fibromyalgia pain, both with and without comorbid depression. Studies also show that the drug continues to be effective for at least one year.

Researchers don't understand exactly how this drug works. However, a 2015 study (Wang) suggests that dampens spontaneous pain signals that result from nerve damage (neuropathy). One theory of fibromyalgia pain is that it involves neuropathy in the small nerves near the surface of your skin. If that's true, it could be why Cymbalta is often effective against our pain.

In that study, Cymbalta appeared to alleviate two pain types that are typical of fibromyalgia: hyperalgesia and allodynia. Hyperalgesia is what "turns up the volume" of our pain, while allodynia is pain from things that normally don't cause pain, such as light pressure.

Dosage

The recommended Cymbalta dosage is 60 mg, taken once a day. It's generally started at 30 mg a day and then increased to 60 mg after about a week.

Doses higher than this aren't believed to be more effective for fibromyalgia, and they are associated with a higher risk of side effects.

People who want to stop taking this drug should talk to their healthcare provider about the proper way to gradually wean off of it; stopping suddenly is dangerous. Your healthcare provider may also be able to help you lessen withdrawal symptoms.

Side Effects

Cymbalta is associated with numerous possible side effects. Those that you should report to your healthcare provider right away include:

• Allergic reactions (rash, itching or hives, swelling of the face, lips or tongue)
• Blood pressure changes
• Confusion
• Dizziness and/or loss of balance
• Fast talking, excited feelings, or out-of-control actions
• Rapid, irregular heartbeat
• Fever
• Hallucinations or loss of contact with reality
• Seizures
• Diarrhea, vomiting
• Suicidal thoughts or other mood changes
• Dark urine
• Unusual bleeding or bruising

Side effects of Cymbalta that don't usually require medical attention include:

• Blurred vision
• Appetite changes
• Changes in sex drive or performance
• Headache
• Increased sweating
• Nausea

Is Cymbalta Right for You?

If you're interested in trying Cymbalta, talk to your healthcare provider. Be sure to carefully weigh the pros and cons and look into any possible negative interactions with other drugs you're taking.

It's a good idea, with any medication, to have a list of possible side effects handy. You may want to let people close to you know about serious side effects, such as seizures, loss of contact with reality, or suicidal thoughts, so that they know what's happening, just in case.