Duloxetine (Cymbalta): Drug Uses, Warnings, Dosage, & More

What Is Duloxetine (Cymbalta)?

Duloxetine is an SNRI medication that is used for a variety of mental/physical disorders. SNRI medications are serotonin-norepinephrine reuptake inhibitors, which allow more serotonin and norepinephrine in the central nervous system. Patients can be started on duloxetine as the first-line treatment for their depression/anxiety. Similarly, physicians may use duloxetine if patients have depression along with fibromyalgia. It is always recommended that patients take part in therapy along with duloxetine usage.

Duloxetine is FDA-approved to treat:¹

• Depression
• Anxiety
• Fibromyalgia
• Chronic musculoskeletal pain
• Diabetic peripheral neuropathy

Duloxetine is also sometimes used off-label. Off-label means that it is not FDA-approved, but a doctor can use it for treating a particular condition because they believe the medication may offer a benefit. Common off-label uses include as a medication for chemotherapy-induced peripheral neuropathy or nerve damage outside of the brain and spinal cord

SSRI and SNRI medications differ in chemical structure but are still first-line treatments for many mental illnesses. They are often grouped because they will make you feel similarly to how other antidepressants make you feel. SSRI medications only work on serotonin, while SNRI medications work on serotonin and norepinephrine in the central nervous system. Duloxetine is unique among SNRI medications as it is known to cause the most side effects of nausea.

Duloxetine, like many other antidepressant medications, does come with a black box warning for patients who are 24 years old or younger. There is an increased risk of suicidal ideation for children, adolescents, and young adults.

History of Duloxetine

Duloxetine was FDA-approved for use in 2004 as the brand name Cymbalta. It was developed by Eli Lilly and Company and was first discovered for its practical use during the depression in 1993. It is currently still FDA-approved and in good standing to be sold in European and North American countries both as Cymbalta and in generic form as duloxetine.

Duloxetine Doses & Delivery Methods

Duloxetine comes as a delayed-release capsule and pellets. The appropriate duloxetine dosage depends on the condition being treated. Providers may elect to start at a lower dose of medication and slowly increase dosages after a few months of use if they have not seen a positive effect. The prescriber may also decrease the dosage if adverse effects are too prominent.

Some typical dosages for duloxetine include:¹

• 40 mg once daily
• 30 mg once daily
• 60 mg once daily

Patients should only adjust medication dosage and timings after a discussion with their physician. It is crucial to take medications as prescribed.

Duloxetine Warnings & Associated Risks

Despite duloxetine being generally well tolerated, anyone considering it themselves should know about its potential risks. Because duloxetine affects norepinephrine, it can have a stimulating effect and is not tolerated well by some people with anxiety as it can increase their symptoms.

Similarly, patients taking other antidepressants/medications that increase serotonin (such as SSRIs or SNRIs) should not take duloxetine due to the risk of serotonin syndrome. Patients diagnosed with bipolar disorder should also not take duloxetine as it can increase their risk of manic episodes.

Duloxetine should not be taken by populations who are or have a history of:¹

• Allergic reactions to duloxetine
• Glaucoma
• Bipolar disorder
• Blood pressure or heart palpitations
• Suicidal ideation
• Pregnant or trying to get pregnant
• Liver disease
• Taking other antidepressants
• End-stage renal disease

You must talk with a doctor if you have any of the above to see if they think sertraline is the right and safe medication for you.

Side Effects of Duloxetine

Duloxetine is generally well tolerated. However, there are common side effects to watch for, such as nausea or vomiting. Most patients will have this naturally resolved. However, others may not be able to tolerate it and require different medications. You should mention any side effects you experience to your doctor. They may suggest dosage adjustment or switching to other medications. It is important to recognize that this is not a comprehensive list of possible side effects with duloxetine.

Common duloxetine side effects may include:

• Nausea
• Vomiting
• Constipation
• Diarrhea
• Palpitations
• Increased blood pressure
• Anorgasmia/sexual impotence
• Headache
• Increased Sweating
• Sleepiness/somnolence

Severe side effects of duloxetine that may require immediate attention include:¹

• Serotonin syndrome
• Severe skin reactions
• Seizures
• Manic episodes
• Suicidal ideation
• Low salt levels
• Liver failure
• Palpitations
• Irregular heartbeat
• Arrhythmias

Allergic Reactions to Duloxetine

Allergic reactions can happen with any medication. Patients can be allergic to duloxetine as well. Patients who had tried duloxetine before and had an allergic reaction should consider other medications. It is always essential to check for rashes, hives, and red itchy eyes and report them to your physician. If you feel short of breath or believe that you are having an anaphylactic reaction, you should call 911 and seek immediate care at your nearest emergency room.

Interactions With Duloxetine

Taking certain medications, herbs, or supplements alongside duloxetine can change how duloxetine works in your body or increase the risk for serious side effects. This article does not consider all the possible interactions. Please let your doctor, psychiatrists, and pharmacists know about all the products you currently use, such as prescription medication, nonprescription drugs, and herbal supplements. Do not start, stop, or change the dosage of any medicines without your doctor’s approval.

Duloxetine works by increasing serotonin and norepinephrine in the brain. If mixed with other medications that increase serotonin, it can lead to serotonin syndrome. This can happen with certain herbal medicines as well.

Although this is not a comprehensive list, substances that may interact with duloxetine include:¹

• Drugs that cause bleeding
• Other SSRIs
• Other SNRI medications
• MAO inhibitor medications
• Marijuana
• Muscle relaxers
• Antiarrhythmic drugs

What to Do If You Overdose on Cymbalta

Cymbalta overdose can occur, and it is dangerous. This often occurs as a result of mixing the medication with other substances. When duloxetine is abused with other medications, it can lead to severe reactions. Duloxetine overdose can result in serotonin syndrome, heart rhythm issues, and seizures. It is advised that you call 9-1-1 or go to the nearest emergency room if you suspect you or someone else has overdosed on duloxetine.

What If I Miss a Dose of Cymbalta?

Duloxetine should be taken as prescribed until you speak to your physician about making medication changes. However, life happens, and you may miss a dose. It is recommended to take the dose when you remember or skip it if it is time for the second dose of the medication.

It is common for patients to stop the medication before the end date of the medicine because they feel better. However, there is an increased chance of depression/anxiety reappearing if medication is stopped prematurely. Patients that want to taper themselves off should speak to their doctor about a tapering dose of medication. It is not advised to stop duloxetine immediately due to the risk of antidepressant discontinuation syndrome. Antidepressant discontinuation syndrome can present with flu-like symptoms, nausea, and vomiting.

Questions to Ask Your Health Team

Millions of people use duloxetine to help them cope with their depression/anxiety. It may be a suitable medication for you as well. It is worth considering this medication if therapy alone does not help your depression/anxiety. Similarly, it is worth considering this medication if SSRI or other SNRI medications do not help. It can be used as a first-line pharmaceutical treatment for your depression/anxiety.

Questions to ask your care team about before taking duloxetine include:

• Is it safe to take duloxetine with my other medications?
• Will my insurance cover duloxetine or Cymbalta?
• Does my medical history increase my risk of side effects?
• How long can I expect side effects to last?
• What side effects should I seek immediate medical attention for?
• How often should I see you for checkups while taking duloxetine?
• Should I let my therapist know I am taking this medication?
• What should I do if I want to stop taking duloxetine?
• What is the dosage of my medication?
• How often should I take my medication?
• How often should I come for dose adjustments to my medication?
• How do Cymbalta vs Effexor compare for depression treatment?

Final Thoughts

Duloxetine is an SNRI medication that individuals can take for various psychiatric conditions. It is commonly used in conjunction with therapy. It is not a controlled substance and is not addictive. Duloxetine is an excellent option for many patients who have depression/anxiety. It can cause severe side effects and should be used with caution. It is essential to talk to your physician to see if duloxetine is a good option for you.