Cymbalta for Fibromyalgia Treatment
What Is Cymbalta?
Cymbalta (duloxetine) is an antidepressant used for the treatment of fibromyalgia. Fibromyalgia is a chronic disorder that causes widespread muscle pain and tenderness, trouble sleeping, and overwhelming tiredness.
Cymbalta belongs to a class of medications called serotonin and norepinephrine reuptake inhibitors (SNRIs). The FDA previously approved Cymbalta for the treatment of depression, generalized anxiety disorder, and diabetic peripheral neuropathic pain. The agency approved Cymbalta for the management of fibromyalgia in adults in June 2008.
A similar medication, called Savella (milnacipran), gained FDA approval in early 2009.
How Does Cymbalta Work?
Scientists are not exactly certain how Cymbalta helps make patients with fibromyalgia feel better; fibromyalgia itself is poorly understood. Many believe the pain is due to changes in the nervous system which cause nerve cells to fire off too many signals along pain pathways. This makes a person overly sensitive to things that would normally not be painful.
Researchers think that Cymbalta helps calm down these pain signals by increasing the level of two naturally occurring substances called serotonin and norepinephrine. These substances, which are found in the brain and other parts of the nervous system, can affect mood and are believed to help control and suppress feelings of pain. Cymbalta and other SNRIs block serotonin and norepinephrine from re-entering cells, and therefore increase the levels of these substances. This process is thought to improve mood and relieve pain in patients with fibromyalgia.
How Do You Take Cymbalta?
Cymbalta is a capsule that you take by mouth once a day. The recommended dose is 60 milligrams a day. However, your doctor will likely tell you to take 30 milligrams a day for the first week, before increasing you to the full dose. It is important to keep in mind that there is no evidence to suggest that taking more than 60 milligrams a day will further reduce your pain. In fact, doing so increases your chances of side effects.
You should not suddenly stop taking this medicine. Doing so may cause unpleasant side effects, including nausea and headache. If you wish or need to stop taking Cymbalta, your doctor will tell you how to reduce your dose gradually over time.
Benefits of Cymbalta
In clinical trials, Cymbalta significantly and quickly improved pain. More than half of the patients with fibromyalgia said they felt much better within one week. Pain relief may be greater in patients who also have existing depression, although those without depression also have a significant improvement in symptoms.
Other benefits of Cymbalta:
- Pain relief is proven to be significant for at least three months of treatment. However treatment should be based on your individual response.
- Less pain allows you to get back to your daily routine.
- Better sleep leads to improved quality of life.
- More refreshing sleep may allow muscle tissues to heal.
Also, SNRIs often have less bothersome side effects than tricyclic antidepressants (such as amitriptyline), which are sometimes prescribed to those with fibromyalgia.
The most common side effects for Cymbalta are:
- Dry mouth
Other side effects that may occur include:
- Decreased appetite (may include anorexia)
- Decreased sex drive
- Drowsiness or sleepiness
- Increased sweating
- Jitters, nervousness, or restlessness (agitation)
- Urinary hesitation
You may feel dizzy upon standing when you first start taking Cymbalta or when your dose is increased. This is due to a drop in blood pressure, and is known as orthostatic hypotension. Your health care provider may want to check your blood pressure from time to time while you are taking Cymbalta.
Risks and Warnings
Cymbalta and other antidepressants may increase the risk for suicidalthoughts and behaviors in people under age 24. After you are prescribed Cymbalta, your doctor will monitor you closely for unusual behavior changes, new or worsening signs of depression, or suicidal thoughts.
Cymbalta may cause a drop in salt (sodium) levels in the blood, a potentially life-threatening condition called hyponatremia. Older adults, particularly those who take diuretics (“water pills”) are more likely to develop this complication. Hyponatremia can cause headaches, confusion, weakness, and in severe cases can lead to fainting, seizures, coma, and death.
Some patients taking Cymbalta have developed liver problems. In rare cases, this has lead to liver failure and death. Contact your health careprovider immediately if you develop any of the following symptoms while taking Cymbalta:
- Dark colored urine
- Pain in the right, upper belly area
- Unexplained flu-like symptoms
- Yellow skin or eyes (jaundice)
In rare cases, a life-threatening condition called serotonin syndrome has occurred in patients who have taken Cymbalta. Serotonin syndrome most often results when someone takes two or more medications that increase the body’s serotonin levels at the same time. You need serotonin for your brain and nerve cells to function, but too much of it can be dangerous. Serotonin syndrome can lead to rapid changes in blood pressure, muscle rigidity, seizures, and even death.
This is why it is so important that your health care providers know what medications you are taking. Always tell them about all the medicines you take, including over-the-counter drugs and herbs and supplements.
Drugs that may interact with Cymbalta and cause serotonin syndrome include:
- Cough medicines that contain dextromethorphan
- Monoamine oxidase inhibitors (MAOIs)
- Nausea and heartburn medications such as metoclopramide (Reglan) and ondansetron (Zofran)
- Pain medications, including meperidine (Demerol, a painkiller) and tramadol (Ultram)
- St. John’s wort
- Triptans, used to treat migraine headaches
Other drugs may also interact with Cymbalta, including:
- Blood thinners, including warfarin, aspirin, and nonsteroidal anti-inflammatory drugs (NSAIDs). Taking Cymbalta with such medications may increase your chances for bleeding events.
Before You Take Cymbalta
Tell your doctor about any other medical conditions you may have. The drug should be prescribed with caution in those who have:
- A history of seizures or mania
- Conditions that slow gastric emptying (sometimes occurs in those with diabetes)
- Diabetes (Cymbalta may effect blood sugar levels)
- High blood pressure or heart disease
- Liver disease
- Kidney disease
Who Should Not Take Cymbalta?
You should not take Cymbalta if you:
- Are taking a medication called thioridazine
- Are taking a medicine called MAOI or have used one in the last 14 days
- Have uncontrolled narrow-angle glaucoma
In animal studies Cymbalta has demonstrated adverse effects on a developing fetus. No adequate or well-controlled studies of the drug have been performed in pregnant or breastfeeding women. Women who are breastfeeding, pregnant, or planning to become pregnant should talk to their doctor about whether or not Cymbalta is right for them. You should only take Cymbalta if the benefits outweigh the risks.