Cymbalta (duloxetine) can cause side effects that range from mild daily nuisances to much more serious health issues. The most common Cymbalta side effects include nausea, dry mouth, sleepiness, fatigue, constipation, loss of appetite, increased sweating, and dizziness. Duloxetine, sold under the brand name Cymbalta among others, [1] is a medication used to treat major depressive disorder, generalized anxiety disorder, obsessive–compulsive disorder, fibromyalgia, neuropathic pain, and other types of chronic pain. [9][10] It is taken by mouth. Cymbalta (duloxetine) is a prescription drug for anxiety, pain from diabetic neuropathy, and other conditions. Learn about side effects, dosage, uses, and more. Cymbalta should be administered at a total dose of 60 mg once daily. Patients should be periodically reassessed to determine the need for maintenance treatment and the appropriate dose for such. Cymbalta (duloxetine) is a selective serotonin and norepinephrine reuptake inhibitor (SNRI) used for treating depression, anxiety disorder, and pain associated with diabetic peripheral neuropathy or fibromyalgia. What Are Side Effects of Cymbalta? Cymbalta may cause serious side effects including: Cymbalta is a selective serotonin and norepinephrine reuptake inhibitor antidepressant (SSNRI). Duloxetine affects chemicals in the brain that may be unbalanced in people with depression. Cymbalta is used to treat major depressive disorder in adults. Duloxetine is used to treat depression and anxiety. It is also used for pain caused by nerve damage associated with diabetes (diabetic peripheral neuropathy). Duloxetine is also used to treat fibromyalgia (muscle pain and stiffness) and chronic (long-lasting) pain that is related to muscles and bones. Cymbalta is used to treat or manage Major Depressive Disorder (MDD), Generalized Anxiety Disorder (GAD), Diabetic Peripheral Neuropathic Pain, Fibromyalgia, and Chronic Musculoskeletal Pain. Find patient medical information for Duloxetine (Cymbalta, Drizalma Sprinkle) on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user ratings Duloxetine (Cymbalta) is a type of antidepressant called an SNRI, or serotonin and norepinephrine reuptake inhibitor. Most people take it by mouth once a day, but some with depression might take it twice a day. Side effects include nausea, headache, and dry mouth.