An oral liquid medicine for spinal muscular atrophy
Risdiplam
An oral liquid medicine used to treat spinal muscular atrophy, an inherited muscle-weakening condition.
What is Risdiplam?
Risdiplam is a specialist medicine used to treat spinal muscular atrophy, an inherited condition that weakens the muscles used for moving, breathing and swallowing. It works by helping the body make more of a protein (SMN) that nerve and muscle cells need to survive and work. Unlike some other treatments it is taken by mouth as a liquid, which can be given at home. It is a long-term treatment that needs specialist supervision. Because of possible effects on a developing baby and on fertility, careful advice is given around pregnancy and contraception.
Education and reference only. This is a plain-language guide to Risdiplam — 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
Risdiplam is a medicine used to treat spinal muscular atrophy, a rare inherited condition in which a lack of a protein called SMN leads to progressive weakening of the muscles, affecting movement and sometimes breathing and swallowing. It is one of the treatments aimed at the underlying cause rather than just the symptoms. A notable feature is that it is taken by mouth as a liquid, so it does not need injections into the spine or a vein, and it can often be given at home. It is started and supervised by a specialist neuromuscular team.
How it works
People with spinal muscular atrophy do not make enough of the survival motor neuron (SMN) protein, which nerve and muscle cells need. A back-up gene called SMN2 can make some of this protein, but normally not enough. Risdiplam changes the way the SMN2 gene's message is processed (a step called splicing) so that more working SMN protein is produced throughout the body. By raising SMN protein levels, it helps preserve nerve and muscle function over time. Because it works steadily, it is taken every day as a long-term treatment.
Company & origin
Originated / developed by: Specialist manufacturer.
A specialist medicine used in the UK to treat spinal muscular atrophy, taken by mouth as a liquid rather than by injection.
Practical use
How to take Risdiplam
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Take it by mouth as a liquid once a day, usually at about the same time, often after a meal as advised.
- Use the special oral syringe provided to measure each dose accurately, and rinse it after use.
- Drink some water after taking it to make sure the whole dose has been swallowed.
- Do not stop taking it without specialist advice, as it is a long-term treatment that works over time.
- Discuss contraception, pregnancy and breastfeeding with your team, as there are cautions around having children.
Weighing it up
Advantages & disadvantages of Risdiplam
Advantages
- Treats the underlying cause of spinal muscular atrophy by helping the body make more SMN protein.
- Taken by mouth as a liquid, avoiding injections into the spine or a vein.
- Can often be given at home, which is more convenient for families.
Disadvantages
- A long-term daily treatment that must be taken consistently to keep working.
- Requires cautions around pregnancy and contraception, and possible effects on fertility.
- Can interact with some other medicines, so careful review is needed.
Practical use
Good to know
Risdiplam is taken as a liquid by mouth, usually once a day, often after a meal, and it is important to use the special oral syringe provided and to take it at about the same time each day. It is a long-term treatment that works gradually to preserve muscle and nerve function, so it needs to be taken consistently and reviewed by the specialist team. Two important safety points relate to having children: in laboratory studies it could harm a developing baby, so effective contraception is advised during treatment and for a period afterwards, and there have been concerns about possible effects on fertility, which the specialist team will discuss. Because it can interact with certain other medicines, it is important to give a full list of everything you take. Anyone who is pregnant, planning a pregnancy or breastfeeding should discuss this carefully with their team.
Who should not take it / use with caution
- People who have had a serious allergic reaction to risdiplam should not take it.
- It is generally avoided in pregnancy and breastfeeding unless the specialist team advises otherwise, because of possible harm to a baby.
- It should only be used under a specialist neuromuscular service that provides monitoring and advice.
Monitoring
- Reviewing muscle strength and function over time to judge how well it is working.
- Checking for side effects and discussing contraception and pregnancy plans.
- Reviewing other medicines for possible interactions.
Side effects
- Fever, diarrhoea or a rash, particularly earlier in treatment.
- Mouth ulcers, joint pain or urinary infections in some people.
- In infants, problems such as chest infections may occur as part of the condition and are watched for by the team.
Key interactions
- It can affect the levels of some other medicines handled by certain transporters in the body, so a full medicines list is important.
- Tell your team about all medicines and supplements, as interactions may need the treatment to be reviewed.
- Effective contraception is advised alongside it, and pregnancy plans should be discussed.
Available as: An oral liquid (solution) taken by mouth, measured with a special syringe.
Answers
Risdiplam: frequently asked questions
What is risdiplam used for?
It is used to treat spinal muscular atrophy, an inherited condition that weakens the muscles, by helping the body make more of the SMN protein that nerve and muscle cells need.
How is it taken?
It is taken by mouth as a liquid, usually once a day, measured with a special oral syringe, and can often be given at home.
Why is contraception important with it?
Laboratory studies suggested it could harm a developing baby, so effective contraception is advised during treatment and for a period afterwards.
Does it cure spinal muscular atrophy?
No. It does not cure the condition, but by raising SMN protein levels it helps preserve muscle and nerve function, so it is taken as a long-term treatment.
Can it affect fertility?
There have been concerns about possible effects on fertility, so this is something your specialist team will discuss with you before and during treatment.
Authoritative sources
- BNF
- NICE CKS
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