Published on 25 April 2022

Taking Duloxetine And Gabapentin Together?

Cymbalta (Duloxetine) duloxetine-and-gabapentin
Table of Contents

According to statics, 75 million Americans have chronic pain that lasts for more than three to six months, making it one of the most prevalent and crippling health issues in the country today. Although chronic pain is a reason for seeking medical attention, it is frequently not adequately managed, leaving patients vulnerable to the toxic or addictive side effects of currently available drugs.

Pain management with antidepressants has been used for many years. Tricyclic antidepressants have historically been the most popular antidepressants for managing chronic pain. An SNRI, duloxetine hydrochloride, was first patented in 1990 and became available in the U.S. in 2004 to treat depression and diabetic peripheral neuropathy (DPN). Inhibiting the reuptake of norepinephrine and serotonin, like TCAs, is how Duloxetine works.

Neuropathic pain and other types of chronic pain have also been managed with anticonvulsants. The anticonvulsant drug gabapentin was first developed in the 1970s. In the USA, it has been accessible as a generic since 2004 after receiving FDA clearance in 1993. They exert their pharmacologic effects at numerous potential pain transmission locations. With its efficacy in neuropathic pain, Gabapentin (adjuvant therapy for partial seizures) became more widely used.

Can you take Duloxetine and Gabapentin together? Let us see what happens when you take Duloxetine and Gabapentin together.

What is Duloxetine?

Duloxetine is a Selective and Norepinephrine Reuptake Inhibitor Antidepressant (SSNRI). Duloxetine treats major depressive and general Anxiety disorders in adults and children at least seven years old. It is a prescribed medicine. 

It is also used to treat nerve pain caused by diabetes in adults (diabetic neuropathy) or chronic muscle or joint pain (such as low back and osteoarthritis pain). The brand name of Duloxetine is Cymbalta, Drizalama Sprinkle, and Irenka.

What is Gabapentin?

Gabapentin is an anti-epileptic drug, also called an anticonvulsant. Gabapentin is used to tackle neuropathic pain (nerve pain) caused by the herpes virus or shingles (herpes zoster). 

Gabapentin is also used to treat Restless Legs Syndrome (RLS) and partial seizures in adults and children at least three years old. The brand name of Gabapentin are Gralise, Horizant, Neurontin, Gabarone.

Mechanism of Duloxetine

Duloxetine treats depression and Anxiety by inhibiting serotonin and norepinephrine reuptake, integrating two therapeutic processes in a single drug. Additionally, Duloxetine raises dopamine levels in the prefrontal brain.

The blockage of norepinephrine transporters is the mechanism of action for the rise in dopamine levels. These transporters can function on dopamine and norepinephrine because they have a strong affinity for dopamine. As a result, blocking norepinephrine transporters may result in a rise in dopamine. The prefrontal cortex, which lacks dopamine transporters and mainly relies on norepinephrine transporters for reuptake, is the location of this surge in dopamine.

Duloxetine increases signaling between noradrenergic and serotonergic neurons along the descending spinal pathway in neuropathic and chronic pain syndromes. These descending neurons block the dorsal horn neurons' ability to fire, preventing the brain from receiving excessive input. A lack of these inhibitory signals causes the brain to receive too much information, resulting in pain.

Mechanism of Gabapentin

Although Gabapentin resembles GABA in structure, it does not affect the synthesis or absorption of GABA and does not attach to GABA receptors. The way gabapentin works are that it has a strong affinity for binding sites in the brain that correspond to the existence of voltage-gated calcium channels, namely alpha-2-delta-1. Blocking excitatory neurotransmitters in the presynaptic region is believed to be responsible for epileptogenesis.

Gabapentin raises the amount of serotonin in the whole blood in healthy people.

Forms and Strengths


Duloxetine is available in forms and strengths of:

  • Oral delayed-release capsule: Duloxetine is available in delayed-release capsule form in 20mg, 30mg, 40mg, and 60mg strengths.


Gabapentin is available in forms and strengths of:

  • Tablets: Gabapentin is available in 300- and 600 mg tablets (Gralise) and 600- and 800 mg tablets (Neurontin or generic Gabapentin.
  • Oral Solution: Gabapentin is available in oral solution, which contains 250 mg of Gabapentin per 5 ml (50 mg per ml), Neurontin, or generic Gabapentin.
  • Capsules: Gabapentin is available in tablets as 100, 300, and 400 mg gelatin capsules (Neurontin or generic Gabapentin).
  • Gabapentin Enacafrbil: Gabapentin enacarbil is available in 300 and 600 mg extended-release tablets (Horizant).

Study Of Duloxetine And Gabapentin

Aim: In this study, the efficacy of Duloxetine and Gabapentin in patients with moderate to severe knee O.A. was studied by bringing in several patients to get the reports.

Method: In this trial, 150 patients with moderate to severe knee O.A. were brought in and were randomly allocated to receive Duloxetine 30mg and Gabapentin 300mg, all twice a day for 12 weeks. The Pain severity was measured before, at two weeks, 1onemonth, and 3 months after intervention using a visual ananalogcale (VAS) and functional status using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC).

Results: The WOMAC total and its subscale score were lower in Duloxetine compared to Gabapentin in 2 weeks and 1 month after the intervention. However, there were no significant differences at the end of the third month. Both Gabapentin and Duloxetine significantly reduced the pain.

Conclusion: At the end of the trial, Gabapentin and Duloxetine have similar and acceptable effects in pain reduction and functional improvement in patients with knee O.A. The impact of Duloxetine began in the first week, while the effects of Gabapentin began gradually and were best at the end of the third month.

Possible Side Effects

Both Gabapentin and Duloxetine are associated with many side effects ranging from standard to severe, and some of the side effects are as listed below:

Some common side effects of Gabapentin are: Some severe side effects of Gabapentin are:
Blurred vision Chest pain
Cold or flu symptoms Black tarry stools
Fever Loss of memory
Nausea and vomiting Swollen glands
Congestion Depression and mood swings
Constipation Cough
Hostility Sore throat
Dry eyes Weakness


Some common side-effects of Duloxetine are: Some severe side effects of Duloxetine are:
Constipation Sexual dysfunction
Vomiting Frequent urination
Weight loss Colitis
Loss of appetite Stomach pain

Can You Take Duloxetine And Gabapentin Together?

Yes, Gabapentin and Duloxetine have no reason to be taken together, so there are no issues if they were to be taken together. Still, Gabapentin and Duloxetine both have side effects that can make you tired and sleepy, so if an individual accepts them together, they must be aware of the adverse side effects.

Frequently Asked Questions

Duloxetine usually takes 2 to 4 weeks to work. It may take longer if you're taking it for nerve pain.
In people with primary insomnia, Gabapentin improves slow-wave sleep. By increasing sleep efficiency and reducing spontaneous arousal, Gabapentin also raises sleep quality. These imply that Gabapentin might help treat primary insomnia.
People who use Duloxetine frequently report experiencing brain zaps, concentration issues, and short-term memory loss. Long-term side effects of Gabapentin include respiratory failure, weaker muscles, and memory loss.
Duloxetine can also cause seizures in vulnerable individuals, which could decrease the effectiveness of drugs used to manage attacks, like Gabapentin.

Drug Interactions 

Treatment with Duloxetine might occasionally cause the blood sodium level to drop; this condition is known as hyponatremia, and using Duloxetine with Gabapentin can increase that risk. Duloxetine can cause seizures in some patients, which may reduce the effectiveness of drugs used to control seizures, like Gabapentin.

How Does It Work In Your Body?

Gabapentin: Gabapentin is known to pass through the blood-brain barrier freely, acts on neurotransmitters, and affects chemicals and nerves in the body that cause seizures and various types of pain.

Duloxetine: Duloxetine is known to increase the amount of norepinephrine and serotonin in the small gaps between the neuron for a few microseconds. For the treatment of depression, the actual response by the cell-binding drug takes 3-6 weeks for full effect. 

Who should not take it?


Gabapentin can cause severe breathing problems, especially if you already suffer from any breathing disorder or use any medication that can make you drowsy or slow your breathing. Then, it is essential to consult your doctor before taking Gabapentin.


Taking Duloxetine by an individual who has used an MAO inhibitor such as isocarboxazid, linezolid, methylene blue injection, phenelzine, tranylcypromine, or others may result in a dangerous or adverse reaction.


Duloxetine and Gabapentin 

For women who are breastfeeding: This medication might pass into bosom milk. Assuming you take this medication while you breastfeed, your child might have symptoms of the drug. Let your primary care physician know if you wish to breastfeed. You might have to choose whether to breastfeed or take this medication.

When taken with alcohol: There is significant interaction between Cymbalta (Duloxetine) and liquor in people with a background marked by generous liquor admission or misuse. It doesn't appear to pose a particularly significant risk to social consumers (although an alert is prompted).

The answer, however, is that it is not wise to combine liquor and Gabapentin. Liquor reduces relaxation because it is a focused sensory system depressant. It is also possible for Gabapentin to impair a person's sleep. However, it's not generally medication-related with deadly excess; it is possibly dangerous to toast overabundance while taking Gabapentin.

For pregnant women: Duloxetine and Gabapentin are considered class C pregnancy drugs, and there are not enough studies and tests done on humans for these medications. It's suggested to consult your doctor before taking this medication.

When taken on an empty stomach: Duloxetine is best endured when taken later a supper. The adequacy of the particular serotonin and norepinephrine reuptake inhibitor energizer duloxetine doesn't vary when patients with sorrow take it on a vacant stomach or following a feast, as indicated by concentrating on outcomes distributed in Clinical Pharmacology in Drug Development. On the other hand, Gabapentin can be taken with or without food.

Medical Conditions:


These are some of the medical conditions to look for before taking Duloxetine:

For people with liver disease: Try not to take this medication if you have a persistent liver infection or cirrhosis of the liver. You might experience difficulty cleaning the drug from your body. This can prompt further liver harm.

For people with kidney disease: Try not to take this medication, assuming you have severe kidney illness or again if you get dialysis. Your kidneys might experience difficulty eliminating the drug from your body. This could prompt the development of the medication and increase the danger of incidental effects.

For people with diabetes: This medication might influence your glucose levels. Assuming you have diabetes, your PCP might need you to screen your levels more intently and may have to change the measurements of your diabetes prescription.

For people with bipolar disorder: This medication might cause mania or hypomania. If you or somebody in your family has bipolar confusion, tell your primary care physician before beginning Duloxetine.

For people with high blood pressure: This medication might expand your circulatory strain. On the off chance that you, as of now, have hypertension, let your PCP know before beginning Duloxetine.


These are some of the medical conditions to look after before taking Gabapentin:

For people with epilepsy: Try not to quit taking Gabapentin suddenly. Doing this can build your danger of having a condition called status epilepticus. This is a health-related crisis during which short or long seizures happen for 30 minutes or more.

For people with kidney problems: Your body treats this medication more leisurely than ordinary. This might make the medication increment to hazardous levels in your body. Converse with your PCP concerning whether this medication is alright for you.

Bottom Line From Practical Anxiety Solutions

Millions of Americans continue to experience chronic pain every day. Clinicians need better alternative medication classes because current treatments for chronic pain are frequently ineffective and constrained by side effects, tolerance, and even addiction. Certain anticonvulsants and antidepressants are effective in treating chronic pain conditions. Compared to TCAs and first-generation anticonvulsants, newer drugs like Duloxetine, Gabapentin, and pregabalin successfully cure pain with more tolerable side-effect profiles.

Gabapentin and Duloxetine are bogus that perform the best in their fields when taken as prescribed by your doctor. There are not many differences between them. If you experience any adverse side effects, consult your doctor. Take the medications exactly as directed and follow the instructions provided by your healthcare provider.

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