Duloxetine is a Serotonin and Noradrenaline reuptake inhibitor (SNRI)


Duloxetine is available in 30mg or 60mg hard gastro-resistant capsules.
UPDATE: I have recently been advised to increase to 120mg a day and have heard of others being advised to do this also.

How it works

According to research, most people with Fibromyalgia are known to have an abnormally low supply of serotonin. This is a neurotransmitter that sends messages to the vital organs via the blood chemistry. Serotonin interacts with substance P, to determine pain levels and when released, it has a similar effect to Noradrenaline, in that it lightens mood and helps reduce pain levels. Serotonin and Noradrenaline are then reabsorbed back into the nerve cells and no longer have these beneficial effects. Duloxetine works by preventing Serotonin and Noradrenaline being reabsorbed back into the nerve cells in the brain. This helps prolong both the mood lightening effects of Serotonin and Noradrenaline and their beneficial effect on pain.

Side Effects

Feeling Sleepy
Feeling sick
Dry mouth
Lack of appetite
Trouble sleeping
Feeling agitated
Lower sex drive including difficulty or failure to reach orgasm
Unusual dreams
Feeling sluggish
Numbness including pricking or tingling of the skin
Blurred eyesight
Feeling the heart pounding in the chest
Increased blood pressure and flushing
Increased yawning
Stomach pain
Being sick
Indigestion and wind
Increased sweating and itchy rash
Muscle pain, muscle spasm
Painfully urination
Problems getting an erection, changes in ejaculation
Weight loss

There are other side effects but I’ve only listed those above 1%, as it would have made a long list. As with all drugs there are side effects which should be discussed with a doctor.

Other information

Cymbalta is not licensed for fibromyalgia in the UK, however some consultants will prescribe it for off licence use. I have known it to be used to treat pain in people with Diabetes and is used to treat stress incontinence in older women. Due to the latter, I did have an awkward conversation with my pharmacist when I first used it, as I fit the visual profile of a young male. We both found the situation very amusing. I have suffered “crushing” sensations in my legs for the last few years, which became almost constant, however, using this drug stopped them overnight and although they can still occur they are very rare.

Care must be taken if you have depression alongside fibromyalgia, due to both the way the drug works and with what other drugs it should not be used alongside, including St John Wort. There is a theoretical risk of serotonin syndrome with this drug, especially if you take it alongside other drugs that increase the level of serotonin in the body.


Duloxetine on patient.co.uk
Duloxetine on netdoctor.co.uk

This page will contain information on medications used in the treatment of Fibromyalgia and some of my personal experiences using them. This page is for information only and is not medical advice and everyone considering taking any medication should discuss the matter with their doctor first. If you have been prescribed any of these drugs, make sure you read the documentation with them, as this section is not meant to be a substitute for this important process.