Duloxetine is the generic equivalent of Cymbalta®.

By law, a generic drug must be the same as its brand name counterpart in terms of active ingredient, dosage, safety, effectiveness, strength, stability, and quality. A generic may, however, differ in its inactive ingredients (i.e. flavoring, fillers, and preservatives).

Duloxetine (Cymbalta®) does come with serious warnings. These include:

• Increased risk of suicidal thoughts or actions*

• Serotonin syndrome—a rare, but potentially life-threatening condition that occurs when there’s too much serotonin in the brain

• Withdrawal symptoms—abrupt discontinuation of treatment can cause nausea, anxiety, confusion, and headache.

• Liver problems, liver damage

• Abnormal bleeding problems

• Manic episodes or hypomania in patients with bipolar disorder

• Seizures

• High blood pressure or changes in blood pressure—must be monitored periodically

• Severe skin reactions

• Glaucoma

• Increases in blood sugar

• Risk of falls in older patients

If any of the above concern you, speak with your doctor or pharmacist about your perceived risk and other treatment options that exist.

*This warning is a boxed warning. A boxed warning is the most serious type of medication warning assigned by the FDA.

Duloxetine is an SNRI (serotonin and norepinephrine reuptake inhibitor). It works by blocking the brain’s absorption of norepinephrine and serotonin, “feed good” chemicals in your brain. The end result? An increased level of norepinephrine and serotonin in your brain, which is thought to improve mood and pain.

Duloxetine is FDA approved for the treatment of:

• Major depressive disorder (MDD) or depression

• Generalized anxiety disorder (GAD)

• Diabetic neuropathy pain

• Fibromyalgia

• Chronic musculoskeletal pain

Amitriptyline may also be used off-label for nerve pain.

The most common side effects of duloxetine include:

• Nausea

• Dry mouth

• Drowsiness, sleepiness

• Fatigue

• Constipation

• Decreased appetitie

• Sweating

• Altered sex drive

• Weight loss, weight gain

• Small increases in heart rate

• Loss of appetite

Side effects may improve over time as your body adjusts to the medicine.

This list doesn’t represent all possible side effects (or serious side effects) of duloxetine. If you’re experiencing any ongoing, bothersome side effect(s), tell your healthcare provider right away.

If you’d like to learn more, speak with your doctor or pharmacist. The Food and Drug Administration (FDA) also has a helpful medication guide for duloxetine here.

Duloxetine can interact with some prescription medication and supplements. It’s always recommended to give both your doctor and pharmacy an updated list of everything you’re taking, so drug interactions can be identified.

Some medicines and supplements duloxetine can interact with include:

• SSRIs (selective serotonin reuptake inhibitors): citalopram, sertraline, fluoxetine, paroxetine

• Monoamine oxidase inhibitors (MAOIs): selegiline, phenelzine, linezolid, methylene blue, tranylcypromine, isocarboxazid

• SNRIs (serotonin and norepinephrine reuptake inhibitors): desvenlafaxine, venlafaxine, milnacipran

• Triptans: sumatriptan, eletriptan, naratriptan

• Arrhythmia medications: propafenone, flecainide

• Alcohol

• NSAIDs: aspirin, ibuprofen

• Warfarin

• Tramadol

• Cimetidine

• St. John’s Wort

• Ciprofloxacin

This list doesn’t represent all the drugs that may not be safe to take with duloxetine. If you’re unsure whether a certain drug or supplement can be taken with duloxetine, seek medical advice from your doctor or pharmacist. The FDA also has a helpful medication guide for duloxetine here.

If you accidentally miss your dose of duloxetine, take the dose as soon as you remember. If it’s almost time for your next dose (within 2 hours), skip the missed dose and take your next dose at the usual time. Don't take 2 doses at the same time or extra doses.

Duloxetine may be taken with or without food. Take each capsule whole. Avoid crushing, chewing, or opening the capsule.

During pregnancy: The safety of duloxetine use during pregnancy isn’t well established.

While breastfeeding: The safety of duloxetine in infants is unknown. Use of this drug while nursing isn’t recommended.

It’s important to treat mental health-related conditions when pregnant or nursing, as untreated depression, anxiety, or other mental illnesses can harm both you and baby. Always let your provider know if you’re pregnant or breastfeeding, so you can discuss the risks and benefits of taking Cymbalta (duloxetine).

It’s recommended to avoid or limit the use of alcohol when taking duloxetine. Liver failure has been reported in patients taking duloxetine and the risk is much higher for patients with substantial alcohol use.