[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Pharmacology](https://durgical.com/en/pharmacology/) › [Spinal muscular atrophy (SMA) therapies](https://durgical.com/en/pharmacology/classes/spinal-muscular-atrophy-therapies/) › Risdiplam # Risdiplam ## Spinal muscular atrophy (SMA) therapies? Spinal muscular atrophy (SMA) therapies First oral drug for spinal muscular atrophy: a small molecule that modifies SMN2 splicing to raise full-length SMN protein. It may harm the fetus. Updated Nov 1, 2026 ## Quick facts **Group** [Spinal muscular atrophy (SMA) therapies](https://durgical.com/en/pharmacology/classes/spinal-muscular-atrophy-therapies/) **Target** SMN2 pre-mRNA splicing **Used for** Spinal muscular atrophy **Key effects** Fever · Diarrhoea · Rash and mouth ulcers **Monitor** Motor milestones · Fever **ATC** M09AX10 No doses: the clinician sets them by the current guideline. On this page - The basics Mechanism of action - Indications - Adverse effects - Pharmacokinetics - Memory aid - Safety Contraindications - Key interactions - What is monitored - Administration and safety - Pregnancy and breastfeeding - Nursing care - Study Test yourself - Connections Connections ## Mechanism of action ◆**SMN2 pre-mRNA splicing**Risdiplam ⓘ The figure shows risdiplam bound to an RNA duplex that models 5′-splice-site recognition, the splicing step it modifies; it is RNA, not a protein. **Target in 3D:** SMN2 pre-mRNA splicing. PDB structure 8R62 (RCSB PDB, public domain). [View the structure at RCSB PDB](https://www.rcsb.org/structure/8R62) · Drag to rotate · pinch to zoom Risdiplam is a survival of motor neuron 2 (SMN2)-directed RNA splicing modifier. Taken by mouth, it changes how SMN2 pre-mRNA is spliced so that more full-length mRNA is produced. More full-length SMN protein is made, which supports motor neurons and improves muscle strength and movement. - Taken by mouth once a day - Acts on SMN2 pre-mRNA splicing - More full-length SMN mRNA is produced - More SMN protein: better motor function ## Indications - Spinal muscular atrophy, infantile-onset and later-onset [Spinal muscular atrophy →](https://durgical.com/en/conditions/spinal-muscular-atrophy/) ## Adverse effects ### Common - Fever - Diarrhoea, constipation and vomiting - Rash and mouth ulcers - Joint pain - Urinary and upper respiratory tract infections, pneumonia in infants ### Serious (rare, important) - Possible harm to the fetus ## Contraindications - Hypersensitivity to risdiplam or to any of its ingredients ## Key interactions **Substrates of multidrug and toxin extrusion (MATE) transporters** Risdiplam may raise their plasma levels; the combination is avoided. ## What is monitored - Pregnancy test before starting when relevant - Motor milestones and motor-function scales - Fever, diarrhoea, rash and infections ## Administration and safety - The oral solution is prepared by the pharmacist and measured with an oral syringe; it is given soon after drawing it up. - In breastfed infants it is given before or after a feed, never mixed with formula or milk. - Tablets are swallowed whole or dispersed only in non-chlorinated drinking water as instructed. - A dose is not repeated if vomited; the next dose is given at the usual time. ## Pregnancy and breastfeeding It may harm the fetus: a pregnancy test may be required before starting, and contraception is used during treatment and for at least one month afterwards. ## Nursing care - Teach carers to measure the solution with the oral syringe and to rinse with water after the dose. - Discuss effective contraception during treatment and for at least a month after. - Watch for fever, rash, mouth ulcers, diarrhoea and signs of infection. - Check the medication list for MATE transporter substrates. ## Pharmacokinetics **Absorption** Oral solution or tablet, once daily, with or without food. ## Memory aid RISdiplam = «Rescue In Syrup»: the oral SMN2 splicing fixer; avoid pregnancy and MATE substrates. ## Test yourself Think of the answer, then tap the question to see it. ## What kind of drug is risdiplam? An oral small molecule that modifies SMN2 RNA splicing to increase full-length SMN protein. ## What was new about risdiplam when it was approved? It was the first oral drug for spinal muscular atrophy. ## Which pregnancy advice comes with risdiplam? It may harm the fetus; a pregnancy test may be needed and contraception is used during treatment and for at least one month after. ## Which transporter substrates should be avoided with risdiplam? Substrates of multidrug and toxin extrusion (MATE) transporters, whose levels risdiplam may raise. [Add to my cards (4)](https://durgical.app/estudiar/?add=/en/pharmacology/risdiplam/) [More Pharmacology questions →](https://durgical.com/en/practice/?f=pharmacology) ## Connections ## Related drugs 2 - [Nusinersen](https://durgical.com/en/pharmacology/nusinersen/) - [Onasemnogene abeparvovec](https://durgical.com/en/pharmacology/onasemnogene-abeparvovec/) ## Related conditions 1 - [Spinal muscular atrophy](https://durgical.com/en/conditions/spinal-muscular-atrophy/) [← Back to the class: Spinal muscular atrophy (SMA) therapies](https://durgical.com/en/pharmacology/classes/spinal-muscular-atrophy-therapies/) Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given. Sources: [Risdiplam: MedlinePlus Drug Information](https://medlineplus.gov/druginfo/meds/a625064.html) (MedlinePlus (U.S. National Library of Medicine), 2025); [FDA Approves Oral Treatment for Spinal Muscular Atrophy](https://www.fda.gov/news-events/press-announcements/fda-approves-oral-treatment-spinal-muscular-atrophy) (U.S. Food and Drug Administration, 2020); [RCSB PDB - 8R62: Solution structure of Risdiplam bound to the RNA duplex formed upon 5'-splice site recognition](https://www.rcsb.org/structure/8R62) (RCSB Protein Data Bank, 2024); [ATCDDD - ATC/DDD Index](https://atcddd.fhi.no/atc_ddd_index/?code=M09AX10) (WHO Collaborating Centre for Drug Statistics Methodology, 2026). ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/pharmacology/risdiplam/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/pharmacology/risdiplam/