An SNRI used mainly for fibromyalgia
Milnacipran
An SNRI used mainly to ease the pain of fibromyalgia, and as an antidepressant in some countries.
What is Milnacipran?
Milnacipran is an SNRI (a serotonin and noradrenaline reuptake inhibitor), used mainly to ease the pain and other symptoms of fibromyalgia, and as an antidepressant in some countries. It is taken by mouth. It can raise blood pressure and heart rate, so these are checked, and stopping it suddenly can cause withdrawal effects, so it is reduced gradually. Like other similar medicines, young people need watching for changes in mood, and there is a small risk of serotonin syndrome if combined with certain other medicines.
Education and reference only. This is a plain-language guide to Milnacipran — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Milnacipran is a medicine in the SNRI group, meaning it acts on two brain chemicals, serotonin and noradrenaline. Its main use in many places is to help with fibromyalgia, a long-term condition causing widespread pain, tiredness and tenderness, where it can ease pain and improve day-to-day function. In some countries it is also used as an antidepressant. It is taken by mouth, usually built up gradually to the right dose, and it is a medicine taken regularly rather than only when symptoms flare.
How it works
Milnacipran increases the activity of serotonin and noradrenaline, two chemical messengers in the nervous system. In fibromyalgia, these chemicals are involved in how the body processes pain signals, so boosting them is thought to turn down the pain and improve symptoms such as low energy. The same effect on these messengers is what gives it an antidepressant action where it is used for depression. Because it acts on noradrenaline, it can also nudge up blood pressure and heart rate, which is why these are monitored.
Company & origin
Originated / developed by: Various manufacturers.
An SNRI medicine used for fibromyalgia, and for depression in some countries, taken by mouth.
What it treats
Conditions Milnacipran is used for
Practical use
How to take Milnacipran
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Take it by mouth as prescribed, usually built up gradually to the right dose.
- Take it regularly to get the benefit; it can take a few weeks to work fully.
- Do not stop it suddenly, as this can cause withdrawal effects; reduce it slowly with your prescriber's guidance.
- Expect your blood pressure and heart rate to be checked, especially when starting.
- Tell your prescriber about all other medicines, as some can interact and raise the risk of serotonin syndrome.
Weighing it up
Advantages & disadvantages of Milnacipran
Advantages
- Can ease the widespread pain and improve function in fibromyalgia.
- Also works as an antidepressant where it is used for that purpose.
- Taken by mouth and used as a regular treatment.
Disadvantages
- Can raise blood pressure and heart rate, which need checking.
- Stopping it suddenly can cause withdrawal effects, so it must be reduced gradually.
- Carries a small risk of serotonin syndrome with certain other medicines, and young people need monitoring for mood changes.
Practical use
Good to know
Milnacipran is usually started at a low dose and built up, and it can take several weeks to feel the full benefit, so it is worth sticking with it unless side effects are a problem. Two practical safety points stand out: it can raise blood pressure and heart rate, so these are checked, especially early on; and it should not be stopped suddenly, because doing so can cause withdrawal effects such as dizziness, irritability and flu-like feelings, so it is reduced slowly under guidance. As with other antidepressant-type medicines, anyone under about twenty-five should be watched for any worsening of mood or thoughts of self-harm, particularly at the start. There is also a small risk of a reaction called serotonin syndrome if it is combined with other medicines that raise serotonin, so always tell your prescriber what else you take.
Who should not take it / use with caution
- People who have had a serious allergic reaction to milnacipran should not take it.
- It must not be taken with, or close to, medicines called MAOIs because of the risk of a serious reaction.
- It is used with caution in people with uncontrolled high blood pressure, certain heart problems, or narrow-angle glaucoma.
- It is used with care in people with liver or kidney problems, under medical guidance.
Monitoring
- Checking blood pressure and heart rate, especially when starting or changing the dose.
- Reviewing how well symptoms respond and watching for side effects.
- Watching for any worsening of mood or thoughts of self-harm, particularly in younger people.
Side effects
- Nausea, especially when first starting.
- A rise in blood pressure or heart rate.
- Headache, sweating, constipation or trouble sleeping.
- Rarely but seriously, serotonin syndrome, or worsening mood and thoughts of self-harm, which need urgent attention.
Key interactions
- It must not be combined with MAOIs, and care is needed with other medicines that raise serotonin, because of serotonin-syndrome risk.
- Medicines that thin the blood may raise bleeding risk when taken with it.
- Tell your prescriber about all medicines, including over-the-counter and herbal products such as St John's wort.
Available as: Tablets or capsules taken by mouth.
Answers
Milnacipran: frequently asked questions
What is milnacipran used for?
It is used mainly to ease the pain and symptoms of fibromyalgia, and as an antidepressant in some countries; it acts on the chemicals serotonin and noradrenaline.
Why are my blood pressure and pulse checked?
Milnacipran can raise blood pressure and heart rate, so these are checked, especially when you first start or the dose changes.
Can I stop it suddenly?
No. Stopping suddenly can cause withdrawal effects such as dizziness and flu-like feelings, so it should be reduced gradually with your prescriber's help.
How long does it take to work?
It can take several weeks to feel the full benefit, so it is usually worth continuing unless you have troublesome side effects.
What is serotonin syndrome?
It is a rare but serious reaction from too much serotonin activity, which can happen if milnacipran is combined with certain other medicines, so tell your prescriber everything you take.
The wider class
About SNRI (serotonin and noradrenaline reuptake inhibitor)
Milnacipran belongs to the snri (serotonin and noradrenaline reuptake inhibitor) class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
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Authoritative sources
- BNF
- NICE CKS
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