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Generic Name: AbobotulinumtoxinA
Class: Other Miscellaneous Therapeutic Agents
Chemical Name: Complex with hemagglutinin (Clostridium botulinum A strain Hall) and neurotoxin (Clostridium botulinum A strain Hall light chain) and protein NTNH (non-toxin non-hemagglutinin) (Clostridium botulinum A strain Hall) neurotoxin (Clostridium botulinum A strain Hall heavy chain)
CAS Number: 953397-35-8


  • Distant Spread of Toxin Effects
  • Effects of any botulinum toxin may spread from local sites of injection, producing symptoms consistent with the mechanism of action of botulinum toxin.381 383 384 (See Distant Spread of Toxin Effects under Cautions.)

  • Symptoms reported hours to weeks following injection.384

  • Swallowing and breathing difficulties may be life-threatening; deaths reported.381 384

  • Children treated for limb spasticity probably at highest risk; however, such effects also can occur in adults, particularly those with underlying predisposing conditions.381 383 384


Neurotoxin produced by Clostridium botulinum; disrupts neurotransmission by inhibiting release of acetylcholine from peripheral cholinergic and ganglionic autonomic nerve terminals.384 388 392 396

Uses for Dysport

Currently, 3 botulinum toxin type A preparations (abobotulinumtoxinA [Dysport], incobotulinumtoxinA [Xeomin], and onabotulinumtoxinA [Botox, Botox Cosmetic]) and one botulinum toxin type B preparation (rimabotulinumtoxinB [Myobloc]) are commercially available in the US.1 2 5 384 403 These preparations are not interchangeable; assay methods used to determine potency of botulinum toxins are specific to each individual manufacturer and/or formulation.1 2 5 381 384 385 391 396 399 403 410

Cervical Dystonia

Management of cervical dystonia (spasmodic torticollis) in adults to decrease severity of abnormal head position and neck pain;384 385 387 designated an orphan drug by FDA for this use.389

Botulinum toxins considered first-line therapy for cervical dystonia.387 391 AbobotulinumtoxinA shown to produce objective and subjective improvements in functional impairment and/or disability.384 385 387 Evidence supporting use largely based on clinical trials of short duration using single injection cycles; additional studies needed to establish long-term efficacy and safety, optimum treatment intervals, and administration techniques (e.g., use of electromyogram [EMG] guidance versus palpation).387

Glabellar Facial Lines

Temporary improvement in appearance of moderate to severe glabellar facial (“frown”) lines associated with corrugator and/or procerus muscle activity in adults <65 years of age.384 393 394

Temporarily weakens corrugator and procerus muscle complex, reducing generation of expression-related glabellar facial lines.393 396 397

Dysport Dosage and Administration


  • Individualize dosage according to patient response and particular condition treated.384 385

  • Do not exceed recommended dose and frequency; excessive and/or unintended neuromuscular weakness may occur if higher than recommended dosages are given.384 Use minimum effective dosage whenever possible to reduce risk of adverse effects.384 388


IM Administration

Administer by IM injection into affected muscles.384

Instructions for reconstitution and administration are specific to each vial size and condition being treated; consult manufacturer's labeling for detailed instructions regarding reconstitution, preparation, and administration.384

Monitor patients for respiratory distress or other possible adverse effects related to spread of botulinum toxin (e.g., dysphagia, dysphonia, unexpected muscle weakness, urinary incontinence, ptosis, double vision, blurred vision, dysarthria).381 384 (See Distant Spread of Toxin Effects under Cautions.)


For cervical dystonia, reconstitute vial labeled as containing 300 or 500 units of lyophilized drug with 0.6 or 1 mL of preservative-free 0.9% sodium chloride injection to provide a solution containing 250 units per 0.5 mL or 500 units per mL, respectively.384 Gently rotate vial until powder is completely dissolved.384

For glabellar facial lines, reconstitute vial labeled as containing 300 units of abobotulinumtoxinA with 1.5 or 2.5 mL of preservative-free 0.9% sodium chloride injection to provide a solution containing 10 units per 0.05 mL or 10 units per 0.08 mL, respectively.384 Use a 21-gauge needle to draw an appropriate amount of diluent into a syringe.384 Insert needle into drug vial at a 45° angle and allow partial vacuum to draw in diluent; do not use vial if vacuum is absent.384 Gently rotate vial until powder is completely dissolved.384

Use reconstituted solutions immediately or store at 2–8°C for up to 4 hours.384 Carefully discard any unused portions as medical waste.384

Injection Techniques (Cervical Dystonia)

Administer total dose per treatment session as several injections divided among affected muscles.384 Use a sterile 23- or 25-gauge needle.384

EMG-guided injections may be helpful in locating target injection sites, particularly for muscles that are difficult to identify by physical examination alone.384

Injection Techniques (Glabellar Facial Lines)

Identify injection sites by palpating for areas of tense muscle mass in the lateral corrugator and vertical procerus muscles while patient is frowning; location, size, and use of such muscles may vary considerably among individuals.384

Administer using a 30-gauge needle.384 Apply digital pressure to superior medial orbital rim while injecting through skin.384

Injections into the medial corrugator muscle should be ≥1 cm above the supraorbital ridge and should not be injected <1 cm above the central eyebrow.384

Avoid injections near the levator palpebrae superioris, especially in individuals with larger brow-depressor complexes.384


Potency of abobotulinumtoxinA expressed in units of biologic activity; each unit is equivalent to the median intraperitoneal lethal dose (LD50) in mice.384 385 393 399

Assay methods used to determine potency of various botulinum toxin preparations are specific to each individual preparation; units of biologic activity of abobotulinumtoxinA cannot be compared with or converted to units of other botulinum toxin preparations.381 384 385 391 396 397 399


Cervical Dystonia

Toxin-naive and previously treated patients: Initially, 500 units as a divided dose among affected muscles.384

In clinical studies, median initial doses injected into the sternocleidomastoid, splenius capitis, trapezius, levator scapulae, scalenus (medius and anterior), semispinalis capitis, and longissimus muscles were 125 units (range 50–350), 200 units (range 75–450), 102.6 units (range 50–300), 105.3 units (range 50–200), 115.5 units (range 50–300), 131.6 units (range 50–250), and 150 units (range 100–200), respectively.384

Adjust total dosage administered in subsequent treatment sessions by increments of 250 units based on patient response.384

Usual duration of response 12–16 weeks or longer; may repeat treatments every 12–16 weeks or longer if symptoms return.384

Glabellar Facial Lines

Manufacturer recommends a total dose of 50 units per treatment session, administered as 10 units (0.05 or 0.08 mL depending on concentration of reconstituted solution) into each of 5 sites: 2 in each corrugator muscle and one in procerus muscle.384

Cosmetic effects usually persist for up to 4 months.384 393 May repeat treatments at intervals of ≥3 months.384

Variable dosing based on gender and muscle mass also has been used in clinical practice.397 Higher doses generally recommended in men versus women due to greater muscle mass in men.397

Prescribing Limits


Cervical Dystonia

Dosage range was 250–1000 units per single treatment session in uncontrolled, open-label clinical studies; safety and efficacy of doses >1000 units not established.384 387

Limit total dose injected into sternocleidomastoid muscle to minimize risk of dysphagia.384 (See Dysphagia/Breathing Difficulties under Cautions.)

Do not repeat treatments more frequently than once every 12 weeks.384

Glabellar Facial Lines

Do not repeat treatments more frequently than once every 3 months.384

Special Populations

Geriatric Patients

Select dosage with caution because of age-related decreases in hepatic, renal, and/or cardiac function and potential for concomitant disease and drug therapy.384 (See Geriatric Use under Cautions.)

Cautions for Dysport


  • Known hypersensitivity to any botulinum toxin preparation or any ingredient in their formulations.384

  • Allergy to cow milk protein.384

  • Infection at proposed injection site(s).384



Distant Spread of Toxin Effects

In some cases, toxin effects may be observed beyond local sites of injection.381 382 383 384 (See Boxed Warning.)

Serious adverse effects consistent with mechanism of botulinum toxin action (e.g., asthenia, generalized muscle weakness, diplopia, ptosis, dysphagia, dysphonia, dysarthria, urinary incontinence, breathing difficulties) reported.371 381 382 383 384 (See Advice to Patients.)

In some cases, severe swallowing and breathing difficulties required hospitalization, mechanical ventilation, or feeding tubes and/or resulted in death.381 384 (See Dysphagia/Breathing Difficulties under Cautions.)

Risk of toxin spread probably highest in children treated for spasticity.381 383 384

Sensitivity Reactions

Hypersensitivity Reactions

Potential risk of hypersensitivity.384 (See Contraindications under Cautions.) Serious hypersensitivity reactions (including anaphylaxis) reported rarely with another preparation of botulinum toxin type A (Botox).1

Intradermal Sensitivity

Possibility of immune reaction following intradermal administration of abobotulinumtoxinA not known.384 Manufacturer states that safety and efficacy of abobotulinumtoxinA for treatment of hyperhidrosis not established.384

Other Warnings/Precautions

Lack of Interchangeability Among Botulinum Toxin Preparations

The method used to determine potency (“units”) of abobotulinumtoxinA is specific to the Dysport preparation;381 384 388 391 396 399 therefore, units of biologic activity for abobotulinumtoxinA cannot be compared with or converted to units of any other botulinum toxin preparation.381 384 385 388 391 393 396 397

Dysphagia/Breathing Difficulties

Risk of dysphagia in patients receiving a botulinum toxin for cervical dystonia.381 383 384 388 Usually a consequence of cervical muscle weakening from local areas of injection, but also may be related to distant spread of toxin effects.381 384 (See Distant Spread of Toxin Effects under Cautions.)

Botulinum toxins may weaken neck muscles that serve as accessory muscles of ventilation, resulting in critical loss of breathing capacity in patients with respiratory disorders.403 Aspiration and death reported as a complication of severe dysphagia.381 383 384 Patients with compromised swallowing function are at increased risk of aspiration.384

Immediate medical attention may be required if sudden difficulties in speech or swallowing develop during or following treatment; such effects may occur hours to weeks after injection.381 384 Gastric feeding tubes may be required in severe cases.381 384

Administration Precautions in Patients with Glabellar Facial Lines

Administer with caution in patients with surgically altered facial anatomy, excessive weakness or atrophy in target muscles, marked facial asymmetry, inflammation, ptosis, excessive dermatochalasis, deep dermal scarring, thick sebaceous skin, or glabellar lines that cannot be substantially decreased manually.384

Clinicians who administer abobotulinumtoxinA should understand the relevant neuromuscular and/or orbital anatomy of the therapeutic area and effects of any changes from surgical alterations.384

Increased incidence of ptosis observed with use of higher than recommended dosages; do not exceed recommended dose and frequency.384 Minimize risk of ptosis with careful monitoring (e.g., examining upper lid for separation or weakness of the levator palpebrae muscle, evaluating range of eyelid excursion, identifying lash ptosis) and adherence to manufacturer's recommended dosages and injection techniques.384 (See Injection Techniques [Glabellar Facial Lines] under Dosage and Administration.)

Preexisting Neuromuscular Disorders

Risk of adverse effects (e.g., severe dysphagia and/or respiratory compromise) with usual dosages of abobotulinumtoxinA appears to be increased in patients with neuromuscular disorders (e.g., peripheral motor neuropathic diseases [e.g., amyotrophic lateral sclerosis, motor neuropathy] or neuromuscular junction disorders [e.g., myasthenia gravis, Lambert-Eaton syndrome]); closely monitor such patients.384

Risk of Viral Transmission

Preparation contains albumin derived from human blood.384 Remote risk of transmission of Creutzfeldt-Jakob disease (CJD) and other viral diseases via albumin component; however, no cases identified to date.384


Potential immunogenicity.384 388 Development of binding or neutralizing antibodies reported in a few patients receiving abobotulinumtoxinA.384 385 Clinical importance not established.384 385

Antibodies may reduce therapeutic effect; however, some patients with neutralizing antibodies continue to respond to the drug.384 385 Certain botulinum toxin preparations may be more likely to elicit an immune response.388

Reporting Adverse Effects or Overdosage

If the patient receives an overdose of abobotulinumtoxinA or the drug is injected into the wrong muscle (i.e., misinjection), contact the local or state health department to process a request for botulism antitoxin through the CDC Drug Service.384 If a response is not received within 30 minutes, contact the CDC Emergency Operations Center directly at 770-488-7100.384 Information about the antitoxin is available at .

Botulism antitoxin will not reverse any botulinum toxin-induced muscle weakness evident at the time of antitoxin administration but may stabilize the deficits.384

Specific Populations


Category C.384


Not known whether distributed into milk.384

Pediatric Use

Manufacturer states that safety and efficacy not established in patients <18 years of age with cervical dystonia.384

Not recommended for cosmetic improvement of glabellar lines in patients <18 years of age.384

Geriatric Use

Insufficient experience in patients ≥65 years of age to determine whether such patients respond differently than younger adults;384 select dosage with caution due to age-related decreases in hepatic, renal, and/or cardiac function and potential for concomitant disease and drug therapy.384

Efficacy for glabellar lines not observed in individuals ≥65 years of age.384 Higher incidence of ocular adverse effects observed in geriatric compared with younger individuals.384


Response rates in African Americans (with Fitzpatrick skin types IV–VI) and Hispanic patients with glabellar facial lines appear to be similar to those observed in the general population.384

Common Adverse Effects

Cervical dystonia: Muscular weakness, dysphagia, dry mouth, injection site discomfort, fatigue, headache, neck pain, musculoskeletal pain, dysphonia, injection site pain, eye disorders (blurred vision, diplopia, reduced visual acuity and accommodation).384 385

Glabellar facial lines: Nasopharyngitis, headache, injection site pain, injection site reaction, upper respiratory tract infection, eyelid edema, ptosis, sinusitis, nausea.384 393 394 395 398

Interactions for Dysport

No formal drug interaction studies to date.384

Specific Drugs




Anticholinergic agents

Potential for additive anticholinergic effects.384

Anti-infective agents interfering with neuromuscular transmission (e.g., aminoglycosides)

Potential for additive botulinum toxin effects384

Closely monitor for adverse effects384

Botulinum toxin treatment, concurrent or sequential

Possible excessive muscle weakness with concurrent or sequential use within several months of abobotulinumtoxinA384

Data on concurrent or sequential use of botulinum toxins lacking384

Muscle relaxants

Potential for excessive muscular weakness when administered prior to, concurrently with, or following abobotulinumtoxinA384

Dysport Pharmacokinetics



Not detectable in peripheral circulation following IM administration.384


Cervical dystonia: Usual duration of effect ≥12–16 weeks or more.384

Glabellar lines: Median duration of effect approximately 85 days following single IM injections of 50 units; reductions in glabellar line severity may be observed for up to 4 months.384 393




Powder for Injection

2–8°C; protect from light.384

Following reconstitution, store at 2–8°C and use within 4 hours; do not freeze.384


  • Purified neurotoxin type A complex produced by fermentation of Clostridium botulinum (Hall strain).384 388 391 396 Differs from other currently available preparations of botulinum toxin type A in molecular size, pharmacologic properties, dosing requirements, and adverse effect profile.384 388 391 396 (See Lack of Interchangeability Among Botulinum Toxin Preparations under Cautions.)

  • Disrupts neurotransmission by inhibiting release of acetylcholine at peripheral cholinergic nerve terminals, inducing a chemical denervation and reduction of muscle activity.384 388 392 396 399

  • Neurotoxic effects occur in 3 phases: binding, internalization, and inhibition of acetylcholine from nerve terminals resulting in neuromuscular blockade.384

  • May also have a direct analgesic effect through modulation of certain peptide neurotransmitters.391

  • Weakness or paralysis of adjacent or distant muscles may occur as a result of toxin diffusion.381 384

  • Recovery of neuromuscular activity occurs slowly through regeneration and recovery of nerve endings.384 396

Advice to Patients

  • Importance of providing a copy of the FDA-approved medication guide and reviewing its contents with every patient.384 400 Instruct patients to read medication guide prior to initiation of therapy and each time prescription is refilled.384 400

  • Advise patients and/or caregivers to seek immediate medical attention if unexpected muscle weakness, swallowing, speech, or respiratory disorders occur, or if any existing symptoms worsen or persist.384 400

  • Advise patients that abobotulinumtoxinA can cause loss of strength, muscle weakness, blurred vision, or drooping eyelids, and that they should not drive a car, operate machinery, or engage in any other potentially hazardous activities during treatment.384 400

  • Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs and dietary or herbal supplements, as well as any concomitant illnesses (e.g., neuromuscular disorders).384 400

  • Importance of women informing their clinician if they are or plan to become pregnant or plan to breast-feed.384 400

  • Importance of informing patients of other important precautionary information.384 400 (See Cautions.)


Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.



Dosage Forms


Brand Names



For injection

300 units



500 units



AHFS DI Essentials. © Copyright, 2016, American Society of Health-System Pharmacists, Inc., 7272 Wisconsin Avenue, Bethesda, Maryland 20814.

Date published: April 27, 2015
Last reviewed: April 27, 2015
Date modified: February 08, 2016


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