Section 09 · Monograph

AbobotulinumtoxinA

Reviewed Nov 2026FDA label

DysportNeurotoxin · injectable

Black Box Warning

DISTANT SPREAD OF TOXIN EFFECT: Postmarketing reports indicate that the effects of Dysport and all botulinum toxin products may spread from the area of injection to produce symptoms consistent with botulinum toxin effects, including asthenia, generalized muscle weakness, diplopia, blurred vision, ptosis, dysphagia, dysphonia, dysarthria, urinary incontinence, and breathing difficulties.
These symptoms have been reported hours to weeks after injection. Swallowing and breathing difficulties can be life-threatening, and there have been reports of death related to spread of toxin effect.
The risk of symptoms is probably greatest in children treated for spasticity, but symptoms can also occur in adults treated for spasticity and other conditions, particularly those with underlying conditions that predispose them to these symptoms.
Cases of spread of effect have been reported at doses comparable to, or lower than, the maximum recommended total dose, in both approved and unapproved (off-label) uses.

Treatment of spasticity in patients 2 years of age and older (adult and pediatric, upper and lower limb).FDA-labeled
Treatment of cervical dystonia in adults.FDA-labeled
Temporary improvement in the appearance of moderate to severe glabellar lines associated with procerus and corrugator muscle activity in adults <65 years of age.FDA-labeled

Sialorrhea (drooling) in adults and children with neurologic disease — not FDA-approved for Dysport (Xeomin holds this indication).Off-label
Post-stroke hemiplegic shoulder pain.Off-label
Focal limb dystonias other than cervical dystonia.Off-label

AbobotulinumtoxinA is a purified botulinum toxin type A neurotoxin complex produced from Clostridium botulinum.
Inhibits release of the neurotransmitter acetylcholine from peripheral cholinergic nerve endings at the presynaptic neuromuscular junction: binds to specific presynaptic membrane receptors, is internalized, and cleaves SNAP-25, blocking exocytosis of acetylcholine-containing vesicles.
This chemodenervation produces localized, reversible reduction in muscle activity/tone; clinical effect typically has onset within days and lasts approximately 12-16 weeks as new nerve terminal sprouts form and neuromuscular transmission is restored.

NOT INTERCHANGEABLE with other botulinum toxin products (onabotulinumtoxinA/Botox, incobotulinumtoxinA/Xeomin, rimabotulinumtoxinB/Myobloc) — Dysport Units are specific to this preparation/assay and cannot be converted via any unit ratio to another product.
Adult upper limb spasticity: total dose individualized by muscle(s) involved, severity, and prior treatment response; typical total dose range 500-1000 Units per treatment session, divided across affected muscles; re-treatment no more frequently than every 12 weeks.
Adult lower limb spasticity: individualized dosing based on the specific muscle pattern (e.g., gastrocnemius, soleus, tibialis posterior); minimum 12-week interval between treatment sessions.
Reconstitute lyophilized powder per labeling; use promptly after reconstitution and administer via IM injection (with EMG/electrical stimulation or ultrasound guidance often used for accurate muscle localization).
Do not exceed the maximum recommended total dose per treatment session or the minimum recommended re-treatment interval (generally 12 weeks) for any indication.

Pediatric lower limb spasticity (age ≥2 years): gastrocnemius 6-9 Units/kg per leg, soleus 4-6 Units/kg per leg; total 10-15 Units/kg unilateral or 20-30 Units/kg bilateral; do not exceed 15 Units/kg unilateral, 30 Units/kg bilateral, or 1000 Units total (whichever is lowest).
Pediatric upper limb spasticity (age ≥2 years): weight-based dosing by muscle; total dose typically 8-16 Units/kg, not to exceed 640 Units.

Known hypersensitivity to botulinum toxin type A preparations or to any component in the formulation.
Known hypersensitivity to cow's milk protein (Dysport contains trace cow's milk protein).
Infection at the proposed injection site(s).

Aminoglycoside antibiotics or other agents that interfere with neuromuscular transmission may potentiate the toxin's effect — use with caution.
Anticholinergic drugs may potentiate systemic anticholinergic-type effects.
Other muscle relaxants (oral antispasmodics) may exacerbate excessive muscle weakness when combined with botulinum toxin.
Concomitant use with other botulinum toxin products is not recommended due to risk of excessive/cumulative neuromuscular weakness; potency units are not interchangeable between products.
Effect of administering different botulinum neurotoxin products at the same time or within several months of each other is unknown and may potentiate distant spread of toxin effect.

Upper limb spasticity (adults, ≥2%): nasopharyngitis, muscular weakness, musculoskeletal pain, dizziness, depression, falls.
Lower limb spasticity: urinary tract infection, muscular weakness, dizziness.
Pediatric lower limb spasticity (≥10%): upper respiratory tract infection, nasopharyngitis, influenza, pharyngitis, cough, pyrexia.
Cervical dystonia (≥5%): muscular weakness, dysphagia, dry mouth, injection-site discomfort, fatigue, headache, musculoskeletal pain.
Glabellar lines: nasopharyngitis, headache, injection-site reaction, eyelid ptosis/edema.
Class effects: dysphagia (can be severe, with risk of aspiration), injection-site pain/bruising, generalized weakness, hypersensitivity reactions (rare), formation of neutralizing antibodies with repeated dosing (may reduce effectiveness).

Monitor for signs/symptoms of distant spread of toxin effect especially in the days to weeks after injection, particularly in pediatric spasticity patients and those with pre-existing neuromuscular disease.
Monitor respiratory status closely in patients with compromised respiratory function, dysphagia, or neuromuscular disease (ALS, myasthenia gravis, Lambert-Eaton syndrome).
Assess treatment response and adverse effects prior to each re-treatment session; do not re-treat sooner than the minimum labeled interval (12 weeks).
Monitor for development of neutralizing antibodies with long-term repeated use.
Monitor injection site for infection/inflammation prior to each treatment.

Pregnancy: No adequate human data. Should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Animal reproduction studies have shown embryo-fetal toxicity at maternally toxic doses.
Lactation: No data on presence in human milk, effects on the breastfed infant, or on milk production; systemic absorption is expected to be low with correct administration, but a risk cannot be excluded.