Cymbalta Side Effects and Withdrawal Symptoms

The body needs about 2 to 4 weeks to adjust to Cymbalta (duloxetine hydrochloride.) It often causes sleep problems. Here’s how to know when to call the doctor.

Cymbalta is the brand name for duloxetine hydrochloride, which in the family of antidepressants called SSRIs (selective serotonin reuptake inhibitors). More familiar drugs like Prozac (fluoxetine) and Paxil (peroxetine) are also in the family. Although many people with depression, fibromyalgia and/or general anxiety disorder (GAD) have been helped with Cymbalta, side effects are common and to be expected.

Normal Side Effects

It can take up to a month for the body to adjust to life with Cymbalta. This means that some normal side effects can last for a month. Some people adjust as soon as ten days. The normal side effects of Cymbalta for new users are:

• Fatigue
• Increase in appetite (although some people have a decrease in appetite)
• Dry mouth
• Constipation or diarrhea (but not both)
• Increase or decrease in sleep
• Loss of sex drive
• Mild nausea that goes away after a couple weeks.

Serious Side Effects

Like any other drug, some people can be allergic to Cymbalta. These serious side effects will show up within the first week of taking it, maybe even after just a couple of days. Contact your doctor immediately if you get any or a combination of these symptoms: 

• Suicidal thoughts
• Sudden nosebleeds
• Sudden, unexplained bruising
• Black, grey or tar-like stools, which usually indicate blood in the stool
• Loss of coordination or inability to stand up
• Vomiting (although some nausea is common, vomiting isn't)
• Hallucinations or mania
• Intensification of anxious symptoms (if you are taking Cymbalta for GAD)
• Seizures
• Shallow breathing or problems breathing

Since you may not be aware if you are hallucinating, it's good to let a trusted person like a parent or friend know that you have started taking Cymbalta. Sometimes the doctor's office will act in this capacity. All they need to do is check up on you once a week to see how you are doing. If you start talking about demons out of the wall, then they can let you know that you are hallucinating and you need to get in contact with your doctor.

Don't Just Stop

You shouldn't stop taking Cymbalta cold turkey, unless you've only been taking it for a week. But over a week, the body starts getting used to Cymbalta and can give you painful withdrawal symptoms if you suddenly quit. You may just need a reduction in dose. Eventually, years down the road when your doctor says the time is right, you can wean yourself off of Cymbalta by gradually reducing your dose. But that's a subject for another article.

Withdrawal symptoms include, but are not limited to:

• Migraines or headaches
• Vomiting
• A strange tingling or burning sensation
• Sweating
• A return of all the symptoms you had before you started taking Cymbalta
• Changes in sleep patterns (too much or too little)
• A marked increase in irritability
• Trembling or shakiness
• Nightmares

These can last from three days to three weeks. Being dependent on Cymbalta or any medicine that helps better your quality of life is not a sign of moral weakness.

References:

The Family Intervention Guide to Mental Illness: Recognizing Symptoms & Getting Treatment. Bodie Morey & Kim T. Mueser, Ph.D. New Harbinger Publications; 2007.

US Food & Drug Administration. "Cymbalta (Duloxetine Delayed-Release Capsules) Medicine Guide."

Wikipedia. “SSRI Discontinuation Syndrome.” 

My Mom has also been taking Cymbalta for yonks.

Image: "A woman diagnosed as suffering from melancholia" Colour lithograph, 1892, after J. Williamson, 1890. Wikimedia Commons.