For anyone living with fibromyalgia, having a healthcare provider suggest an antidepressant may come as a surprise.
But duloxetine (Cymbalta) is approved by the Food and Drug Administration (FDA) to help fibromyalgia patients cope with joint and muscle pain, fatigue, sleep disturbance, and other symptoms.
Since Cymbalta is more commonly prescribed for the treatment of depression and anxiety, it’s natural to wonder how it also works for fibromyalgia.
While you should always discuss any treatment option with your doctor, this article will help you understand more. First we’ll cover how Cymbalta works and if it helps with pain relief.
Then we’ll discuss other uses of Cymbalta, its adverse effects and standard dosage, and other medications that help treat fibromyalgia.
How Does Cymbalta Work?
The underlying cause of fibromyalgia is difficult to understand, but research suggests the condition is caused by excessive nerve stimulation.
The brain’s pain receptors become overstimulated and sensitive.
This can cause you to feel pain or more intense pain in parts of your body even when nothing is causing discomfort.
Cymbalta is a serotonin-norepinephrine reuptake inhibitor (SNRI). It helps levels of the neurotransmitters norepinephrine and serotonin remain higher in the brain by blocking their reabsorption.
People who have fibromyalgia often have low levels of these neurotransmitters, or their brains ineffectively use them.
Norepinephrine and serotonin play a role in the perception of pain, so increasing their levels is thought to dampen the pain response.
Can Cymbalta Reduce Fibromyalgia Pain?
According to animal studies, duloxetine reduces two pain types associated with fibromyalgia: hyperalgesia and allodynia. Hyperalgesia means someone is overly sensitive to pain—smaller discomforts feel like more significant pains to them.
Allodynia is when things that aren’t typically considered painful (like light pressure from brushing your hair or gently rubbing a cotton swab over your skin) feel bothersome and uncomfortable.
Other Uses for Cymbalta
In addition to fibromyalgia, Cymbalta is approved by the FDA to treat the following disorders:
- Major depressive disorder
- Generalized anxiety disorder
- Chronic musculoskeletal pain
- Diabetic peripheral neuropathy
Side Effects of Cymbalta
Most side effects of Cymbalta are usually minor and go away over time.
The most common potential side effects associated with Cymbalta are:
Other potential adverse events include:
- Abdominal pain
- Sexual side effects such as decreased sex drive
If you experience any of the following more serious side effects, contact your doctor immediately:
- High fever
- Flu-like symptoms
- Dark urine
- Rapid heartbeat
- Unusual blisters/peeling skin
- Intense mood swings
- Changes in vision
- Suicidal thoughts
Just like other antidepressants, Cymbalta carries a black box warning indicating that there is increased risk of developing worsening depression, suicidal thinking and behavior.
This occurs most often in children, adolescents, and young adults, but can happen to anyone.
If you or your loved ones are taking this medication or any antidepressant, watch out for the following warning signs that will require immediate medical attention:
- Unusual changes in behavior
- Worsening symptoms of depression including hopelessness, feeling of worthlessness
- Increase in conversations about death
- Thoughts or talk of self-harm
If any of the above symptoms occur, it’s important to seek immediate medical attention.
Cymbalta is not safe for some people with certain medical conditions or who are taking certain medications. Contraindications include:
- Hypersensitivity or allergy to any ingredients in Cymbalta
- MAO inhibitor use within the prior 14 days, such as linezolid or methylene blue
- Severe kidney disease
- Liver disease, including cirrhosis
- Uncontrolled narrow-angle glaucoma
- Alcohol abuse
- Low sodium caused by syndrome of inappropriate ADH secretion (SIADH)
Caution is advised if the following conditions exist:
- Bleeding disorders or current use of NSAIDs, aspirin, or other anticoagulant use
- Hypertension on current blood pressure- medications
- Heart disease
- Seizure disorder
- Bipolar disorder
- Use of other antidepressant medications, pain medications, herbal remedies.
There are other conditions that can predispose to unsafe side effects of any medication, including Cymbalta.
Discuss your medical history and current medications, including over the counter medications, with your healthcare provider, so that the safest decisions on your treatment plan can be made.
Cymbalta Dosage for Fibromyalgia
The dosage of Cymbalta for the treatment of fibromyalgia typically begins at 30 milligrams (mg) a day for a week. Depending on how an individual responds to this, doctors typically increase the dosage to 60 mg daily.
Dosages higher than 60 mg a day provide no additional benefit and instead increase the risk of more serious side effects.
Never suddenly stop taking Cymbalta or discontinue the drug without speaking to your healthcare provider. If you suddenly stop taking the drug, you could experience withdrawal symptoms.
Other Medications that Treat Fibromyalgia
Cymbalta isn’t the only option to treat and help manage fibromyalgia.
Other treatment options include:
- Other SNRI: ilnacipran (Savella) and off-label use of venlaxafine (Effexor)
- Anti-seizure drugs: Gabapentin (Neurontin) and pregabalin (Lyrica) have FDA approval to treat the pain of fibromyalgia.
- Pain relievers: Prescription medication pain relievers like tramadol (Ultram) or over-the-counter (OTC) pain relievers like ibuprofen (Advil, Motrin) and acetaminophen (Tylenol) can also help manage pain.
When to See a Doctor
Contact your doctor if you take Cymbalta for fibromyalgia and:
- Your symptoms of fibromyalgia worsen
- You forget to take a dose of Cymbalta
- You are interested in switching your medication
Seek immediate medical care if you start to experience any of the more serious side effects of Cymbalta (such as hallucinations, high fevers, and intense mood swings).
If you have suicidal thoughts, you can also contact the free and anonymous National Suicide Prevention Lifeline at 800-273-8255 or text the Crisis Text Line (text HOME to 741741).
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Frequently Asked Questions
K Health articles are all written and reviewed by MDs, PhDs, NPs, or PharmDs and are for informational purposes only. This information does not constitute and should not be relied on for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment.
K Health has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references.
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Cymbalta for Fibromyalgia Pain - Predictive Value of Small Fiber Changed. (2019).
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Efficacy of Duloxetine in Patients With Fibromyalgia: Pooled Analysis of 4 Placebo-Controlled Clinical Trials. (2009).
The Local and Systemic Actions of Duloxetine in Allodynia and Hyperalgesia Using a Rat Skin Incision Pain Model. (2015).
A Study of Duloxetine in Fibromyalgia. (2015).