Nusinersen: uses, dosing, side effects & brands
Nusinersen is a medicine sold in the U.S. under one brand. Below: what the FDA label says, every product that contains it, what the pills look like, and its recall record.
Key facts
- Available as
- Injectable
- Sold as
- Spinraza
- Prescription?
- Prescription only
- Generic available?
- Not in our catalog
How nusinersen is dosed
From the FDA label for Spinraza (application NDA209531). Other nusinersen products — different forms, different strengths — are dosed differently. Follow the label for the one you were prescribed.
SPINRAZA is administered intrathecally ( 2.1 ) Recommended Dosage ( 2.1 ) The recommended dosage is one of two options: Low Dose Regimen: Administer one 12 mg loading dose every 14 days for three doses; then a fourth 12 mg loading dose 30 days after the third dose; then administer a 12 mg maintenance dose once every 4 months thereafter. High Dose Regimen: Administer one 50 mg loading dose followed by a second 50 mg loading dose 14 days later; then administer a 28 mg maintenance dose once every 4 months thereafter. Important Preparation and Administration Instructions ( 2.3 ) Allow to warm to room temperature prior to administration Administer within 4 hours of removal from vial Prior to administration, remove 5 mL of cerebrospinal fluid Administer as intrathecal bolus injection over 1 to 3 minutes Laboratory Testing and Monitoring to Assess Safety ( 2.4 ) At baseline and prior to each dose, obtain a platelet count, coagulation laboratory testing, and quantitative spot urine protein testing 2.1 Recommended Dosage SPINRAZA is administered intrathecally by, or under the direction of, healthcare professionals experienced in performing lumbar punctures. Two dosing regimen options for SPINRAZA, which consist of loading followed by maintenance dosages, are presented in Table 1 . Table 1: Recommended Dosage for SPINRAZA Loading Dosages Maintenance Dosage Low Dose Regimen (Low dose…
Nusinersen side effects
The following serious adverse reactions are described in detail in other sections of the labeling: Thrombocytopenia and Coagulation Abnormalities [see Warnings and Precautions ( 5.1 )] Renal Toxicity [see Warnings and Precautions ( 5.2 )] The most common adverse reactions that occurred in at least 20% of SPINRAZA-treated patients who received Low Dose Regimen and occurred at least 5% more frequently than in control patients were: lower respiratory infection and constipation in patients with infantile-onset SMA ( 6.1 ) pyrexia, headache, vomiting, and back pain in patients with later-onset SMA ( 6.1 ) The most common adverse reactions in at least 10% of SPINRAZA-treated patients who received High Dose Regimen and occurred at least 5% more frequently than in historic matched sham-control were: pneumonia, COVID-19, pneumonia aspiration, and malnutrition in patients with infantile-onset SMA ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Biogen at 1-844-477-4672 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of SPINRAZA cannot be directly compared to rates in clinical trials of other drugs and may not reflect the rates observed in practice. SPINRAZA Low Dose Regimen (12 mg loading doses/12 mg maintenance doses) In…
Who shouldn’t take nusinersen
None. None.
Every nusinersen product we track (1)
Same active ingredient — different manufacturer, form, price and FDA recall record. That last one is what our independent score measures.
Only one: Spinraza.
What people report to the FDA about nusinersen
The FDA Adverse Event Reporting System (FAERS) collects reports from patients and clinicians. It holds 3 reports naming nusinersen, and the FDA flagged 67% of those reports as serious. The effects reported most often — leaving out reports about overdose, misuse or the condition being treated, which dominate the raw list for common medicines:
- abdominal pain1 reports
- apnoea1 reports
- mouth ulceration1 reports
- pleural effusion1 reports
- pneumonia1 reports
- sedation complication1 reports
- somnolence1 reports
- upper respiratory tract infection1 reports
Read these as a signal, not a rate. A report does not mean nusinersen caused the effect — anyone can file one, and many describe people taking several medicines for several conditions. Crucially there is no denominator: FAERS does not record how many people took the drug, so these counts cannot be turned into “X% of patients” — a bigger number often just means a more widely used or more talked-about drug. Duplicates exist, and publicity drives reporting. For what is actually established, read the FDA label section above.
Source: openFDA drug/event (FAERS), retrieved July 25, 2026.
Related calculators
Frequently asked questions
What is nusinersen?
Nusinersen is a modified antisense oligonucleotide, where the 2'-hydroxy groups of the ribofuranosyl rings are replaced with 2'-O-2-methoxyethyl groups and the phosphate linkages are replaced with phosphorothioate linkages. Nusinersen binds to a specific sequence in the intron downstream of exon 7 of the SMN2 transcript.
Can you take nusinersen with other medicines?
It depends on the medicine. We check it against the FDA labels rather than guessing: our interaction checker searches each drug's own label for the other and quotes what it says, naming the section it came from. Run nusinersen against whatever else you take — and remember that a label not naming a drug is not the same as that combination being safe.
What forms does nusinersen come in?
Across the brands we track, nusinersen is currently marketed as injectable, per the FDA's National Drug Code Directory. Each form is dosed differently — follow the label for the exact product you were prescribed.
Is there a generic nusinersen?
We do not currently list a generic-labelled nusinersen product. That does not always mean none exists — it means none appears under a generic name in the FDA data we track. Ask your pharmacist.
Cite this page
- APA
- pharmaranks. (2026, July 24). Nusinersen: uses, dosing, side effects & brands. https://pharmaranks.com/drugs/nusinersen
- MLA
- “Nusinersen: uses, dosing, side effects & brands.” pharmaranks, 24 July 2026, https://pharmaranks.com/drugs/nusinersen.
We summarise public FDA and NIH sources — for a clinical claim, cite the primary source we link to as well.
Sources: FDA openFDA drug label, National Drug Code Directory, and Enforcement (recall) database. This page reproduces public FDA data and is not medical advice. Dosing is set by your prescriber.
Read the full FDA label for nusinersen on DailyMed (NIH) ↗.