Duloxetine (Cymbalta): Uses, Warnings and Side Effects

What is duloxetine?

Duloxetine is a medicine used in the treatment of depression, anxiety, and diabetic peripheral neuropathy. The active ingredient is duloxetine hydrochloride.

In the United States, duloxetine is available under brand names including Cymbalta, Irenka, and Drizalma Sprinkle.

How duloxetine works

Duloxetine is a serotonin and noradrenaline reuptake inhibitor. It also weakly inhibits dopamine reuptake and has no significant affinity for histaminergic, dopaminergic, cholinergic, or adrenergic receptors.

Therapeutic uses and dosing information

Duloxetine is taken by mouth.

Adults:

For exact dosing, always check the official leaflet or ask a healthcare professional, since the right regimen depends on the condition being treated and the person’s medical history.

How it is taken

Duloxetine is usually taken once daily, with or without food.

When duloxetine should not be used

The source content lists the following contraindications:

• Hypersensitivity to duloxetine
• Liver disease leading to liver failure
• Severe kidney failure
• Uncontrolled high blood pressure
• Use with irreversible, non-selective MAOIs
• Use with potent CYP1A2 inhibitors such as fluvoxamine, ciprofloxacin, or enoxacin

Warnings and precautions

Duloxetine requires extra caution in some situations. The source content highlights the following:

• Mild or moderate kidney failure
• History of mania or bipolar disorder
• Seizures
• High intraocular pressure or risk of narrow-angle glaucoma
• Conditions that could be affected by increased heart rate or blood pressure
• Use with other antidepressants, substances that affect metabolism, medicines associated with liver damage, oral anticoagulants, or medicines that affect platelet function
• Known bleeding tendency
• Higher risk of hyponatremia, including in older adults, cirrhosis, dehydration, or diuretic treatment
• Monitoring at the start of treatment and after dose changes for suicide risk
• Risk of akathisia or psychomotor restlessness in the first few weeks
• Risk of serotonergic syndrome, especially with other serotonergic medicines or MAOIs

Children and adolescents

The source content states that there are no data on safety and efficacy in children under 18 years for diabetic peripheral neuropathic pain or generalized anxiety disorder, and that duloxetine should not be used in children and adolescents under 18 years for major depressive disorder.

Liver and kidney considerations

Liver failure: Duloxetine is contraindicated in hepatic disease that produces hepatic insufficiency.

Renal insufficiency: Duloxetine is contraindicated in severe renal failure and should be used with caution in mild to moderate renal insufficiency.

Drug interactions

The source content lists these interaction concerns:

• CNS-active medicines: alcohol, benzodiazepines, morphine-like medicines, antipsychotics, phenobarbital, and sedating antihistamines
• CYP2D6 substrates: risperidone, nortriptyline, amitriptyline, imipramine, flecainide, propafenone, and metoprolol
• CYP1A2 inhibitors: fluvoxamine may increase duloxetine levels
• CYP1A2 inducers: may decrease duloxetine concentrations

If you take any prescription medicine, over-the-counter product, or herbal supplement, a pharmacist or doctor should review the combination before use.

Pregnancy and breastfeeding

Pregnancy: The source content says there is no data and that duloxetine should be used only if the benefit outweighs the risk to the fetus.

Breastfeeding: Duloxetine is reported to be very weakly excreted in human breast milk in a study of 6 lactating mothers who did not breastfeed. The estimated infant exposure was approximately 0.14% of the mother’s dose. Because safety in children is unknown, its use during breastfeeding is not recommended in the source content.

Effects on driving and daily activities

Duloxetine can cause sedation and dizziness. If these effects occur, avoid driving, operating machinery, or other potentially hazardous tasks.

Possible adverse reactions and side effects

The source content lists the following adverse reactions:

• Headache, drowsiness, dizziness, lethargy, tremors, paresthesia
• Decreased appetite, insomnia, agitation, decreased libido, anxiety, abnormal orgasms, abnormal dreams
• Blurred vision, tinnitus, palpitations, increased blood pressure
• Flushing, yawning
• Nausea, dry mouth, constipation, diarrhea, abdominal pain, vomiting, dyspepsia, flatulence
• Increased sweating, rash
• Musculoskeletal pain, muscle spasm
• Dysuria, urinary frequency
• Erectile dysfunction, ejaculation disorder, delayed ejaculation
• Falls, fatigue, weight loss
• Rarely: interstitial lung disease

If a side effect is severe, persistent, or worrying, seek medical advice promptly.

What to verify with a doctor or pharmacist

Before using duloxetine, it is sensible to confirm:

• Whether it is appropriate for the condition being treated
• Whether any liver, kidney, blood pressure, eye, seizure, or mood history changes the risk
• Whether any current medicines or supplements could interact
• Whether the official medication guide has condition-specific instructions

Safety reminder

FAQs about duloxetine

Sources and references

This article was rewritten from the supplied source content and cross-references the FDA medication guide and ingredient databases listed below.