OnabotulinumtoxinA

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Solution Reconstituted, Injection [preservative free]:

Botox: 100 units (1 ea); 200 units (1 ea) [contains albumin human]

Solution Reconstituted, Intramuscular:

Botox Cosmetic: 100 units (1 ea) [contains albumin human]

Solution Reconstituted, Intramuscular [preservative free]:

Botox Cosmetic: 50 units (1 ea) [contains albumin human]

Pharmacology

Mechanism of Action

OnabotulinumtoxinA (previously known as botulinum toxin type A) is a neurotoxin produced by Clostridium botulinum, spore-forming anaerobic bacillus, which appears to affect only the presynaptic membrane of the neuromuscular junction in humans, where it prevents calcium-dependent release of acetylcholine and produces a state of denervation. Muscle inactivation persists until new fibrils grow from the nerve and form junction plates on new areas of the muscle-cell walls. Intradetrusor injection affects efferent pathways of detrusor activity by inhibiting release of acetylcholine. Intradermal injection results in temporary sweat gland denervation, reducing local sweating.

Pharmacokinetics/Pharmacodynamics

Absorption

Not expected to be present in peripheral blood at recommended doses following intramuscular (IM) injection

Onset of Action

Blepharospasm: ~3 to 4 days; Cervical dystonia: ~2 weeks; Detrusor overactivity associated with neurologic condition: ~2 weeks; Reduction of glabellar lines (Botox Cosmetic): 1 to 2 days, increasing in intensity during first week; Spasticity: Focal and cerebral palsy related: <2 weeks; Strabismus: ~1 to 2 days

Time to Peak

Blepharospasm: 1 to 2 weeks; Cervical dystonia: ~6 weeks; Spasticity (focal): 4 to 6 weeks; Strabismus: Within first week

Duration of Action

Blepharospasm: ~3 to 4 months; Cervical dystonia: ≤3 to 4 months; Detrusor overactivity associated with neurologic condition: ~42 to 48 weeks; Reduction of glabellar lines (Botox Cosmetic): ~3 to 4 months; Spasticity: ~3 to 3.5 months; Strabismus: ~2 to 6 weeks; Primary axillary hyperhidrosis: 201 days (mean)

Use: Labeled Indications

Axillary hyperhidrosis (Botox):

Treatment of severe primary axillary hyperhidrosis in adults not adequately managed with topical agents.

The safety and effectiveness for hyperhidrosis in other body areas have not been established. Weakness of hand muscles and blepharoptosis may occur in patients who receive onabotulinumtoxinA for palmar hyperhidrosis and facial hyperhidrosis, respectively. Patients should be evaluated for potential causes of secondary hyperhidrosis (eg, hyperthyroidism) to avoid symptomatic treatment of hyperhidrosis without the diagnosis and/or treatment of the underlying disease.

Cervical dystonia (Botox): Treatment of cervical dystonia in patients ≥16 years of age to reduce the severity of abnormal head position and neck pain.

Chronic migraine (Botox): Prophylaxis of chronic migraine headaches (≥15 days/month with headache lasting ≥4 hours/day) in adults.

Glabellar lines (Botox Cosmetic): Temporary improvement in the appearance of moderate to severe glabellar lines associated with corrugator and/or procerus muscle activity in adults.

Forehead lines (Botox Cosmetic): Temporary improvement in the appearance of moderate to severe forehead lines associated with frontalis muscle activity in adults.

Lateral canthal lines (Botox Cosmetic): Temporary improvement in the appearance of moderate to severe lateral canthal lines associated with orbicularis oculi activity in adults.

Overactive bladder (Botox): Treatment of overactive bladder with symptoms of urge urinary incontinence, urgency, and frequency in adults who have an inadequate response to or who are intolerant to an anticholinergic medication.

Spasticity (Botox):

Lower limb:

Adult: Treatment of lower limb spasticity to decrease the severity of increased muscle tone in ankle and toe flexors (gastrocnemius, soleus, tibialis posterior, flexor hallucis longus, and flexor digitorum longus).

Pediatric: Treatment of lower limb spasticity (excluding spasticity caused by cerebral palsy) in pediatric patients 2 to 17 years of age.

Upper limb:

Adult: Treatment of upper limb spasticity to decrease the severity of increased muscle tone in elbow flexors (biceps), wrist flexors (flexor carpi radialis and flexor carpi ulnaris), finger flexors (flexor digitorum profundus and flexor digitorum sublimis), and thumb flexors (adductor pollicis and flexor pollicis longus).

Pediatric: Treatment of upper limb spasticity in pediatric patients 2 to 17 years of age.

Strabismus and blepharospasm associated with dystonia (Botox): Treatment of strabismus and blepharospasm associated with dystonia, including benign essential blepharospasm or VII nerve disorders, in patients ≥12 years of age.

Urinary incontinence due to detrusor overactivity (Botox): Treatment of urinary incontinence due to detrusor overactivity associated with a neurologic condition (eg, spinal cord injury, multiple sclerosis) in adults who have an inadequate response to or are intolerant of an anticholinergic medication.

Canadian labeling: Additional use (not in US labeling): Dynamic equinus foot deformity in pediatric cerebral palsy patients

Use: Off Label

Achalasiabyes

American College of Gastroenterology (ACG) guidelines recommend botulinum toxin for patients with achalasia who are not candidates for pneumatic dilation or surgical myotomy, based on moderate-quality evidence. OnabotulinumtoxinA was the most frequently used product in controlled trials. Controlled trials demonstrate high rates of response (up to 75%) that may decrease over time, with repeat treatments possibly required at 6- to 24-month intervals.

Anal fissuresbyes

Data from controlled trials and a systematic review support the use of botulinum toxin A in the management of anal fissures in patients who have not responded to topical nitrates or calcium channel blockers Samim 2012, Yiannakopoulou 2012.

Guidelines by the American Society of Colon and Rectal Surgeons and a position statement from the Association of Coloproctology of Great Britain and Ireland on the management of anal fissures consider botulinum toxin A injection an option for the treatment of anal fissures in patients who have not responded to first-line therapies. It is important to note that botulinum toxin A formulations are not interchangeable

Raynaud phenomenon, severe, refractory to initial conventional therapyc

Small, noncontrolled trials, case series, and retrospective reviews have suggested some benefit with botulinum toxin A (onabotulinumtoxinA) for severe symptoms associated with primary or secondary Raynaud phenomenon (RP) Motegi 2016, Neumeister 2009, Neumeister 2010, Uppal 2014, Zhang 2015. A small, randomized, double-blind, placebo-controlled trial in patients with scleroderma-associated Raynaud phenomenon also suggested a positive effect in patient-reported clinical measures (a secondary outcome); however, the trial did not show significant improvements in blood flow as measured by laser Doppler imaging (the primary outcome) Bello 2017. A systemic review found insufficient evidence to assess the efficacy of onabotulinumtoxinA in severe RP Żebryk 2016. Experts have recommended that use be reserved for patients with severe RP who have not tolerated or have failed initial conventional therapy Neumeister 2015, Wigley 2018. Additional trials may be necessary to further define the role of onabotulinumtoxinA in this condition.

Sialorrhea (drooling)byes

The use of botulinum toxin A for decreasing or controlling sialorrhea has demonstrated benefit in randomized controlled trials and meta-analyses in patients with various neurological conditions. EFNS guidelines on the clinical management of ALS recommend botulinum toxin A in patients refractory to first-line therapy. An AAN report classifies botulinum toxin A as probably safe and effective in Parkinson-related sialorrhea. Additional study is needed to determine the expected duration of response, potential candidates, optimal dosing regimens, and standardization of injection procedures.

Tardive dyskinesiac

Evidence from small, noncontrolled trials suggests some benefit with botulinum toxin A for treatment of localized tardive dyskinesia (eg, orofacial, head and neck, cervical). Evaluation of data is limited because several studies do not specify what botulinum toxin type A product was used. Use of onabotulinumtoxinA has been evaluated primarily in case reports demonstrating benefit in most patients. AAN clinical practice guidelines find the data inadequate to support or refute the use of botulinum toxin type A for treatment of tardive dyskinesia.

Contraindications

Hypersensitivity to any botulinum toxin preparation or any component of the formulation; infection at the proposed injection site(s).

Botox (only): Intradetrusor injection in patients with overactive bladder or detrusor overactivity associated with a neurologic condition who have a UTI; intradetrusor injection in patients with urinary retention and in patients with postvoid residual urine volume >200 mL who are not routinely performing clean intermittent self-catheterization

Canadian labeling: Additional contraindications (not in US labeling): Intradetrusor injection in patients who are not willing and able to have clean intermittent catheterization (CIC) initiated; intradetrusor injection in patients with a recent history of frequent urinary tract infections.

Dosage and Administration

Dosing: Adult

Note: The lowest recommended dose should be used when initiating treatment (regardless of indication). In adults treated for 1 or more indications, the maximum cumulative dose should be ≤400 units/3 months for Botox or Botox Cosmetic. Canadian labeling recommends a maximum cumulative dose of 6 units/kg (up to 360 units) over 3 months in adult patients receiving additional treatment for noncosmetic indications.

Bladder dysfunction: Intradetrusor: Note: Prophylactic antimicrobial therapy (excluding aminoglycosides) should be administered 1 to 3 days prior to, on the day of, and for 1 to 3 days following onabotulinumtoxinA administration to decrease risk of urinary tract infection (UTI). Discontinue antiplatelet therapy at least 3 days prior to administration.

Detrusor overactivity associated with neurologic condition: 30 injections of 1 mL (recommended concentration: ~6.7 units/mL) for a total dose of 200 units/30 mL (maximum: 200 units); for the final injection, ~1 mL of sterile NS should be injected to ensure that the remaining medication in the needle is delivered to the bladder; may consider re-treatment with diminishing effect but no sooner than 12 weeks from previous administration (median time until second treatment in studies: 42 to 48 weeks).

Overactive bladder: 20 injections of 0.5 mL (recommended concentration: 10 units/mL) for a total dose of 100 units/10 mL (maximum: 100 units); for the final injection, ~1 mL of sterile NS should be injected to ensure that the remaining medication in the needle is delivered to the bladder; may consider re-treatment with diminishing effect but no sooner than 12 weeks from the previous administration (median time until second treatment in studies: ~24 weeks)

Blepharospasm: IM:

Botox: Initial dose: 1.25 to 2.5 units injected into the medial and lateral pretarsal orbicularis oculi of the upper lid and lateral pretarsal orbicularis oculi of lower lid

Dose may be increased up to twice the previous dose if the response from the initial dose lasted ≤2 months; maximum dose per site: 5 units. Tolerance may occur if treatments are given more often than every 3 months, but the effect is not usually permanent. Cumulative dose:

US labeling: ≤200 units in 30-day period

Canadian labeling (not in US labeling): Botox: ≤200 units in 2-month period

Cervical dystonia: IM: For dosing guidance, the mean dose is 236 units (25th to 75th percentile range 198 to 300 units) divided among the affected muscles in patients previously treated with botulinum toxin (maximum: ≤50 units/site). Initial dose in previously untreated patients should be lower. Sequential dosing should be based on the patient's head and neck position, localization of pain, muscle hypertrophy, patient response, and previous adverse reactions. The total dose injected into the sternocleidomastoid muscles should be ≤100 units to decrease the occurrence of dysphagia.

Canadian labeling (not in US labeling): IM: Botox: Effective range of 200 to 360 units has been used in clinical practice; administer no more frequently than every 2 months

Chronic migraine: IM: Administer 5 units/0.1 mL per site. Recommended total dose is 155 units once every 12 weeks. Each 155 unit dose should be equally divided and administered bilaterally, into 31 total sites as described below (refer to prescribing information for specific diagrams of recommended injection sites):

Corrugator: 5 units to each side (2 sites)

Procerus: 5 units (1 site only)

Frontalis: 10 units to each side (divided into 2 sites/side)

Temporalis: 20 units to each side (divided into 4 sites/side)

Occipitalis: 15 units to each side (divided into 3 sites/side)

Cervical paraspinal: 10 units to each side (divided into 2 sites/side)

Trapezius: 15 units to each side (divided into 3 sites/side)

Spasticity: IM: Individualize dose based on patient size, extent, and location of muscle involvement, degree of spasticity, local muscle weakness, and response to prior treatment. May repeat therapy at ≥3 months with appropriate dosage based upon the clinical condition of patient at time of re-treatment. Single session doses of ≤1,200 units (off-label dose) have been reported; however, safety and efficacy of routine use of doses >500 units has not been evaluated (Francisco, 2004). Single site doses of ≤400 units (off-label dose) in a lower limb (off-label use) have been reported (Nalysnyk 2013).

Lower limb spasticity: The lowest recommended starting dose should be used and ≤50 units/site should be administered. Note: Dose listed is total dose administered as divided separate intramuscular injection(s):

Flexor digitorum longus: 50 units (divided into 2 sites)

Flexor hallucis longus: 50 units (divided into 2 sites)

Gastrocnemius lateral head: 75 units (divided into 3 sites)

Gastrocnemius medial head: 75 units (divided into 3 sites)

Soleus: 75 units (divided into 3 sites)

Tibialis posterior: 75 units (divided into 3 sites)

Upper limb spasticity. The lowest recommended starting dose should be used and ≤50 units/site should be administered. Note: Dose listed is total dose administered as individual or separate intramuscular injection(s):

Adductor pollicis: 20 units (1 site)

Biceps brachii: 100 to 200 units (divided into 4 sites)

Flexor digitorum profundus: 30 to 50 units (1 site)

Flexor digitorum sublimes: 30 to 50 units (1 site)

Flexor carpi radialis: 12.5 to 50 units (1 site)

Flexor carpi ulnaris: 12.5 to 50 units (1 site)

Flexor pollicis longus: 20 units (1 site)

Suggested guidelines for the treatment of stroke-related upper limb spasticity: Canadian labeling: Note: Dose listed is total dose administered as individual or separate intramuscular injection(s):

Adductor pollicis: 20 units (1 to 2 sites)

Biceps brachii: 100 to 200 units (up to 4 sites)

Flexor digitorum profundus: 15 to 50 units (1 to 2 sites)

Flexor digitorum sublimes: 15 to 50 units (1 to 2 sites)

Flexor carpi radialis: 15 to 60 units (1 to 2 sites)

Flexor carpi ulnaris: 10 to 50 units (1 to 2 sites)

Flexor pollicis longus: 20 units (1 to 2 sites)

Strabismus: IM: Note: Several minutes prior to injection, administration of local anesthetic and ocular decongestant drops are recommended.

Initial dose:

Vertical muscles and for horizontal strabismus <20 prism diopters: 1.25 to 2.5 units in any one muscle

Horizontal strabismus of 20 to 50 prism diopters: 2.5 to 5 units in any one muscle

Persistent VI nerve palsy ≥1 month: 1.25 to 2.5 units in the medial rectus muscle

Re-examine patients 7 to 14 days after each injection to assess the effect of that dose. Subsequent doses for patients experiencing incomplete paralysis of the target may be increased up to twice the previous administered dose. The maximum recommended dose as a single injection for any one muscle is 25 units. Do not administer subsequent injections until the effects of the previous dose are gone.

Primary axillary hyperhidrosis: Intradermal: 50 units/axilla. Injection area should be defined by standard staining techniques. Injections should be evenly distributed into multiple sites (10 to 15), administered in 0.1 to 0.2 mL aliquots, ~1 to 2 cm apart. May repeat when clinical effect diminishes.

Cosmetic uses:

Reduction of forehead lines

US labeling: IM: When identifying the location of the appropriate injection sites in the frontalis muscle, assess the overall relationship between the size of the subject's forehead and the distribution of frontalis muscle activity. The location, size, and use of the muscles vary markedly among individuals. Inject 0.1 mL (4 units) into 5 injection sites in the frontalis muscle for a total dose of 0.5 mL (20 units) administered no more frequently than every 3 months. Note: Treat forehead lines in conjunction with glabellar lines to reduce the risk of brow ptosis.

Canadian labeling: IM: Inject 2 to 6 units into each of four sites in the frontalis muscle every 1 to 2 cm along either side of forehead crease and 2 to 3 cm above eyebrows for total dose of 24 units.

Reduction of glabellar lines: IM: An effective dose is determined by gross observation of the patient's ability to activate the superficial muscles injected. The location, size, and use of muscles may vary markedly among individuals. Inject 0.1 mL (4 units) dose into each of five sites, two in each corrugator muscle and one in the procerus muscle for a total dose 0.5 mL (20 units) administered no more frequently than every 3 to 4 months. Note: Treatment of adults >65 years is approved in the Canadian labeling.

Reduction of lateral canthus lines:

US labeling: IM: Inject 0.1 mL (4 units) into 3 injection sites per side (6 total injection points) in the lateral orbicularis oculi muscle for a total dose of 0.6 mL (24 units) administered no more frequently than every 3 months.

Canadian labeling: IM: Inject 2 to 6 units into each of 1 to 3 injection sites, lateral to the lateral orbital rim.

Dosing: Geriatric

Initiate therapy at lowest recommended dose. Refer to adult dosing.

Dosing: Pediatric

Note: Potency units are specific to product and assay method utilized; do not interchange botulinum toxin products. Route of administration varies (IM, intradermal, intradetrusor, etc) based on indication; use precaution. The lowest recommended dose should be used when initiating treatment (regardless of indication). Unless otherwise noted in the indication-specific dosing, total maximum dose per 3 months are as follows: In pediatric patients <18 years, the maximum cumulative dose within a 3-month period is 10 units/kg or 340 units, whichever is less, for Botox; in adolescents ≥18 years treated for 1 or more indications, the maximum cumulative dose within a 3-month period should not exceed 400 units for Botox.

Blepharospasm: Children ≥12 years and Adolescents: Botox: IM: Initial: 1.25 to 2.5 units injected into the medial and lateral pretarsal orbicularis oculi of the upper lid and into the lateral pretarsal orbicularis oculi of the lower lid. Dose may be increased up to twice the previous dose if the response from the initial dose is insufficient (ie, effect lasted ≤2 months); maximum dose per site: 5 units. Tolerance may occur if treatments are given more often than every 3 months, but the effect is not usually permanent. Maximum cumulative dose: 200 units in 30-day period.

Cervical dystonia: Adolescents ≥16 years: Botox: IM: For dosing guidance, the mean dose is 236 units (25th to 75th percentile range 198 to 300 units) divided among the affected muscles in patients previously treated with botulinum toxin (maximum: ≤50 units/site). Initial dose in previously untreated patients should be lower. Sequential dosing should be based on the patient's head and neck position, localization of pain, muscle hypertrophy, patient response, and previous adverse reactions. The total dose injected into sternocleidomastoid muscles should be ≤100 units to decrease the occurrence of dysphagia.

Spasticity: Note: Individualize dose based on patient size, extent, and location of muscle involvement, degree of spasticity, local muscle weakness, and response to prior treatment. When treating both upper and lower limb spasticity, the total dose should not exceed 10 units/kg or 340 units total in a 3-month period. May repeat therapy when the therapeutic effect of previous treatment has diminished; generally it should be no sooner than 12 weeks from previous injection.

Upper extremity:

Children ≥2 years and Adolescents ≤17 years: Botox: IM: Usual dose: 3 to 6 units/kg total per session divided up amongst affected muscles; maximum dose per site: 50 units/site; maximum total dose per treatment session in the upper limb: 6 units/kg or 200 units total, whichever is less. Refer to prescribing information for specific diagrams of recommended injection sites.

Adolescents ≥18 years: Botox: IM: 75 to 400 units per treatment session divided among selected muscle groups has been used in clinical trials. Note: The lowest recommended starting dose should be used not to exceed 50 units/site. Dose listed is total dose administered per muscle group and recommendations on dividing the total dose into individual IM injection(s) if applicable; refer to prescribing information for specific diagrams of recommended injection sites.

Lower extremity:

Children ≥18 months and Adolescents:

Lower extremity unrelated to cerebral palsy: Children ≥2 years and Adolescents ≤17 years: Botox: IM: Usual dose: 4 to 8 units/kg total per session divided up amongst affected muscles; maximum dose per site: 50 units/site; maximum total dose per treatment session in the lower limb or visit: 8 units/kg or 300 units total, whichever is less. Refer to prescribing information for specific diagrams of recommended injection sites.

Equinous foot due to cerebral palsy: Limited data available: Children ≥2 years and Adolescents ≤17 years: Botox: IM: Initial: 4 units/kg total dose divided into 2 sites, the lateral and medial heads of the gastrocnemius muscle. For diplegia, the initial dose is 6 units/kg divided between the affected limbs. Repeat doses may be administered with diminishing effect but no sooner than 12 weeks from previous administration (Botox prescribing information [Canada 2018]).

Lower extremity due to cerebral palsy; multilevel approach (multiple muscles): Limited data available; variable dosing regimens reported; optimal dose not established; dosing based on trials and expert recommendations (Aydil 2019; Heinen 2010; Molenaers 2010; Pavone 2016).

Children ≥18 months and Adolescents: Botox: IM: Total dose range: 10 to 30 units/kg divided into multiple muscle groups over multiple injection sites per muscle groups have been reported; maximum dose per site: 50 units/site; maximum total dose per treatment session: 400 units (Aydil 2019; Heinen 2010; Molenaers 2010; Pavone 2016).

The following are reported total dose administered per muscle group to be divided into multiple injections spaced ≥4 to 5 cm (Molenaers 2010; Pavone 2016).

Adolescents ≥18 years: The lowest recommended starting dose should be used and ≤50 units/site should be administered; recommended total dose: 300 to 400 units divided across ankle and toe muscles. Note: Dose listed is total dose administered as divided separate IM injection(s); refer to prescribing information for specific diagrams of recommended injection sites.

Strabismus: Limited data available in patients <12 years of age: Note: Several minutes prior to injection, administration of local anesthetic and ocular decongestant drops are recommended.

Infants and Children 2 months to 11 years (Scott 1990): Botox: IM:

Horizontal or vertical deviations <20 prism diopters: Patients weight ≥6 kg: 1.25 units into any one muscle.

Horizontal or vertical deviations 20 to 50 prism diopters:

Patient weight <6 kg: 1 unit into any one muscle.

Patient weight 6 to 9 kg: 1.25 units into any one muscle.

Patient weight 10 to 12.5 kg: 1.25 to 1.75 units into any one muscle.

Patient weight >12.5 kg: 1.25 to 2.5 units into any one muscle.

Persistent VI nerve palsy of ≥1 month duration:

Patient weight <6 kg: 1 unit into the medial rectus muscle.

Patient weight ≥ 6 kg: 1.25 units into the medial rectus muscle.

Children ≥12 years and Adolescents: Botox: IM:

Initial dose:

Vertical muscles and for horizontal strabismus <20 prism diopters: 1.25 to 2.5 units into any one muscle.

Horizontal strabismus 20 to 50 prism diopters: 2.5 to 5 units into any one muscle.

Persistent VI nerve palsy of ≥1 month duration: 1.25 to 2.5 units into the medial rectus muscle.

Maintenance dose: Re-examine patient 7 to 14 days after each injection to assess the effect of that dose. Subsequent doses for patients experiencing incomplete paralysis of the target may be increased up to twice the previous administered dose; maximum recommended dose as a single injection for any one muscle is 25 units. Do not administer subsequent injections until the effects of the previous dose are gone.

Bladder dysfunction: Adolescents ≥18 years: Botox: Intradetrusor: Note: Prophylactic antimicrobial therapy (excluding aminoglycosides) should be administered 1 to 3 days prior to, on the day of, and for 1 to 3 days following onabotulinumtoxinA administration to decrease risk of urinary tract infection. Discontinue antiplatelet therapy at least 3 days prior to administration.

Detrusor overactivity associated with neurologic condition: 30 injections of 1 mL (recommended concentration: ~6.7 units/mL) for a total dose of 200 units/30 mL (maximum total dose: 200 units); for the final injection, ~1 mL of sterile NS should be injected to ensure that the remaining medication in the needle is delivered to the bladder; may consider re-treatment with diminishing effect but no sooner than 12 weeks from previous administration (median time until second treatment in studies: 42 to 48 weeks).

Overactive bladder: 20 injections of 0.5 mL (recommended concentration: 10 units/mL) for a total dose of 100 units/10 mL (maximum total dose: 100 units); for the final injection, ~1 mL of sterile NS should be injected to ensure that the remaining medication in the needle is delivered to the bladder; may consider re-treatment with diminishing effect but no sooner than 12 weeks from the previous administration (median time until second treatment in studies: ~24 weeks).

Hyperhidrosis, primary axillary: Adolescents ≥18 years: Botox: Intradermal: 50 units/axilla. Injection area should be defined by standard staining techniques. Injections should be evenly distributed into multiple sites (10 to 15), administered in 0.1 to 0.2 mL aliquots, ~1 to 2 cm apart. May repeat when clinical effect diminishes.

Migraine, chronic: Adolescents ≥18 years: Botox: IM: Administer 5 units/0.1 mL per site; recommended total dose: 155 units once every 12 weeks. Each 155 unit dose should be equally divided and administered bilaterally, into 31 total sites as described below (refer to prescribing information for specific diagrams of recommended injection sites):

Corrugator: 5 units to each side (1 site per side).

Procerus: 5 units (1 site only).

Frontalis: 10 units to each side (divided into 2 sites per side).

Temporalis: 20 units to each side (divided into 4 sites per side).

Occipitalis: 15 units to each side (divided into 3 sites per side).

Cervical paraspinal: 10 units to each side (divided into 2 sites per side).

Trapezius: 15 units to each side (divided into 3 sites per side).

Reconstitution

Reconstitute with sterile, preservative-free NS: Slowly inject diluent into the vial and gently mix; discard vial if a vacuum does not pull diluent into the vial. Note: Dilution information (excludes recommendations for preparing the solution for use in detrusor overactivity associated with a neurologic condition [described under separate heading]):

Dilution information for preparing the solution for use in detrusor overactivity associated with a neurologic condition are described separately below:

Botox 50-unit vial: Reconstitute vials with 1 mL of diluent to obtain concentration of 5 units per 0.1 mL; 2 mL of diluent to obtain concentration of 2.5 units per 0.1 mL; 4 mL of diluent to obtain concentration of 1.25 units per 0.1 mL.

Botox 100-unit vial: Reconstitute vials with 1 mL of diluent to obtain concentration of 10 units per 0.1 mL; 2 mL of diluent to obtain concentration of 5 units per 0.1 mL; 4 mL of diluent to obtain concentration of 2.5 units per 0.1 mL; 8 mL of diluent to obtain concentration of 1.25 units per 0.1 mL; 10 mL of diluent to obtain concentration of 1 unit per 0.1 mL.

Botox 200-unit vial: Reconstitute vials with 1 mL of diluent to obtain concentration of 20 units per 0.1 mL; 2 mL of diluent to obtain concentration of 10 units per 0.1 mL; 4 mL of diluent to obtain concentration of 5 units per 0.1 mL; 8 mL of diluent to obtain concentration of 2.5 units per 0.1 mL; 10 mL of diluent to obtain concentration of 2 units per 0.1 mL.

Botox Cosmetic: Reconstitute 50-unit vial with 1.25 mL of diluent or 100-unit vial with 2.5 mL of diluent to obtain concentration of 4 units per 0.1 mL (20 units per 0.5 mL for glabellar lines, 24 units per 0.6 mL for lateral canthal lines and 40 units per 1 mL for forehead lines treated in conjunction with glabellar lines). Reconstitute vial using an appropriate sized needle and syringe by inserting needle into vial at a 45° angle and allowing vacuum to pull diluent into vial (do not use if vacuum has been lost); mix gently. Note: Botox Cosmetic 200-unit vial [CAN; not available in US] may be reconstituted with 5 mL of diluent to obtain concentration of 4 units per 0.1 mL.

Detrusor overactivity associated with a neurologic condition: Dilution recommendations:

100-unit vial: Reconstitute two 100 unit vials, each with 6 mL of preservative-free NS; mix gently. Withdraw 4 mL from each vial into each of two 10 mL syringes; withdraw remaining 2 mL from each vial into the third 10 mL syringe for a total of 4 mL in each of the three 10 mL syringes. To complete dilution, add 6 mL of preservative-free NS into each of the three 10 mL syringes and mix gently; each of the 10 mL syringes will contain 10 mL (~6.7 units/mL) for a total of 200 units.

200-unit vial: Reconstitute with 6 mL of preservative-free NS; mix gently. Withdraw 2 mL from the vial into each of three 10 mL syringes. To complete dilution, add 8 mL of preservative-free NS into each of the three 10 mL syringes and mix gently; each of the 10 mL syringes will contain 10 mL (~6.7 units/mL) for a total of 200 units.

Administration

Bladder dysfunction (including overactive bladder and detrusor overactivity associated with neurologic condition): Intradetrusor: Prophylactic antimicrobial therapy (excluding aminoglycosides) should be administered 1 to 3 days prior to, on the day of, and for 1 to 3 days following onabotulinumtoxinA administration. Discontinue antiplatelet therapy at least 3 days prior to administration. If a local anesthetic is instilled into the bladder prior to treatment, drain bladder and irrigate with normal saline prior to injection. Instill saline into bladder to optimize visualization but avoid overdistention. The injection needle should be primed with ~1 mL of reconstituted onabotulinumtoxinA prior to injection to remove any air. Administer onabotulinumtoxinA via flexible or rigid cystoscope by inserting needle with the recommended volume ~2 mm into the detrusor (avoid the trigone). Injections should be spaced ~1 cm apart. After completion of injections, drain saline from bladder and monitor patient for ≥30 minutes. In overactive bladder patients, a spontaneous void should also occur prior to patient leaving the clinic.

Blepharospasm: Use a 27- or 30-gauge needle without electromyography guidance. Avoid injecting near the levator palpebrae superioris (may decrease ptosis); avoid medial lower lid injections (may decrease diplopia). Apply pressure at the injection site to prevent ecchymosis in the soft eyelid tissues.

Cervical dystonia: Use 25-, 27-, or 30-gauge needle for superficial muscles and a longer 22-gauge needle for deeper musculature; electromyography may help localize the involved muscles.

Chronic migraines: Use a 0.5 inch, 30 gauge needle to administer 5 units/0.1 mL to each of the 31 sites.

Detrusor overactivity associated with neurologic condition: Prophylactic antimicrobial therapy (excluding aminoglycosides) should be administered 1 to 3 days prior to, on the day of, and for 1 to 3 days following onabotulinumtoxinA administration. If a local anesthetic is instilled into the bladder prior to treatment, drain bladder and irrigate with normal saline prior to injection. Instill saline into bladder to optimize visualization but avoid overdistention. Administer onabotulinumtoxinA via flexible or rigid cystoscope by inserting needle ~2 mm into the detrusor. A total of 30 injections (1 mL per injection) should be administered ~1 cm apart. After completion of injections, drain saline from bladder and monitor patient for ≥30 minutes.

Spasticity (cerebral palsy related; Canadian labeling [not in US labeling]): Use a 23- to 26-gauge needle for administration into the medial and lateral heads of the gastrocnemius muscle of the affected limb.

Spasticity (upper or lower limb): Use a 25-, 27-, or 30-gauge needle for superficial muscles and a longer 22-gauge needle for deeper musculature; electromyography or nerve stimulation may help localize the involved muscles.

Strabismus injections: Must use surgical exposure or electromyographic guidance; use the electrical activity recorded from the tip of the injections needle as a guide to placement within the target muscle. Local anesthetic and ocular decongestant should be given before injection. The volume of injection should be 0.05 to 0.15 mL per muscle. Many patients will require additional doses because of inadequate response to initial dose.

Primary axillary hyperhidrosis: Inject each dose intradermally to a depth of ~2 mm and at a 45° angle. Do not inject directly into areas marked in ink (to avoid permanent tattoo effect). Prior to administration, injection area should be defined by standard staining techniques such as Minor's Iodine-Starch Test.

Instructions for Minor's Iodine-Starch Test: Patient should shave underarms and refrain from using deodorants or antiperspirants for 24 hours prior to test. At 30 minutes prior to test, patient should be at rest, no exercise, and not consume hot beverages. Underarm area should be dried and immediately painted with iodine solution. After area dries, lightly sprinkle with starch powder. Gently blow off excess powder. A deep blue-black color will develop over the hyperhidrotic area in ~10 minutes.

Reduction of forehead lines (Botox Cosmetic): For intramuscular use only. Use as 30- to 33-gauge needle. Inject into 5 injection sites in the frontalis muscle. Refer to indication-specific administration information in manufacturer’s location for details on locating injection sites.

Reduction of glabellar lines (Botox Cosmetic): For intramuscular use only. Use a 30- to 33-gauge needle. Inject into each of 5 sites (2 injections in each corrugator muscle and 1 injection in the procerus muscle). Ensure injected volume/dose is accurate and where feasible keep to a minimum. Avoid injection near the levator palpebrae superioris. Refer to indication-specific administration information in manufacturer's location for details on locating injection sites.

Reduction of lateral canthal lines (Botox Cosmetic): For intramuscular use only. Use a 30- to 33-gauge needle and give injections with the needle bevel tip up and oriented away from the eye. Inject into 3 sites per side (6 total injection points) in the lateral orbicularis oculi muscle. Refer to indication-specific administration information in manufacturer's location for details on locating injection sites.

Storage

Store unopened vials under refrigeration at 2°C to 8°C (36°F to 46°F) for up to 36 months or until the expiration date on the vial; extended storage information at room temperature may be available; contact product manufacturer to obtain current recommendations. After reconstitution, store in refrigerator at 2°C to 8°C (36°F to 46°F) and use within 24 hours (does not contain a preservative).

Drug Interactions

Aminoglycosides: May enhance the neuromuscular-blocking effect of Botulinum Toxin-Containing Products. Monitor therapy

Anticholinergic Agents: Botulinum Toxin-Containing Products may enhance the anticholinergic effect of Anticholinergic Agents. Monitor therapy

Botulinum Toxin-Containing Products: May enhance the neuromuscular-blocking effect of other Botulinum Toxin-Containing Products. Monitor therapy

Muscle Relaxants (Centrally Acting): May enhance the adverse/toxic effect of Botulinum Toxin-Containing Products. Specifically, the risk for increased muscle weakness may be enhanced. Monitor therapy

Neuromuscular-Blocking Agents: Botulinum Toxin-Containing Products may enhance the neuromuscular-blocking effect of Neuromuscular-Blocking Agents. Monitor therapy

Adverse Reactions

As reported with adult patients, unless otherwise noted. Adverse effects usually occur in 1 week and may last up to several months.

>10%:

Bladder dysfunction: Genitourinary: Urinary tract infection (18% to 49%), bacteriuria (4% to 18%), urinary retention (6% to 17%), increased postvoid residual urine volume (not requiring catheterization: 3% to 17%)

Cervical dystonia:

Central nervous system: Headache (11%)

Gastrointestinal: Dysphagia (19%)

Neuromuscular & skeletal: Neck pain (11%)

Respiratory: Upper respiratory tract infection (12%)

Upper limb spasticity:

Respiratory: Upper respiratory tract infection (children and adolescents: 10% to 17%)

Other indications (blepharospasm, forehead lines, glabellar lines, lateral canthal lines, primary axillary hyperhidrosis, strabismus):

Central nervous system: Vertical strabismus (17%)

Ophthalmic: Blepharoptosis (strabismus: 1% to 38%; blepharospasm: 21%; forehead lines, glabellar lines: 2% to 3%)

1% to 10%:

Bladder dysfunction:

Central nervous system: Myasthenia (4%), abnormal gait (3%), falling (3%)

Gastrointestinal: Constipation (4%)

Genitourinary: Dysuria (4% to 9%), hematuria (4% to 5%)

Immunologic: Antibody development (neutralizing: 1%)

Neuromuscular & skeletal: Muscle spasm (2%)

Cervical dystonia:

Central nervous system: Dizziness (2% to 10%), drowsiness (2% to 10%), hypertonia (2% to 10%), numbness (2% to 10%), speech disturbance (2% to 10%)

Gastrointestinal: Nausea (2% to 10%), xerostomia (2% to 10%)

Immunologic: Antibody development (1%)

Local: Local soreness/soreness at injection site (2% to 10%)

Neuromuscular & skeletal: Back pain (2% to 10%), stiffness (2% to 10%), asthenia (2% to 10%)

Ophthalmic: Blepharoptosis (2% to 10%), diplopia (2% to 10%)

Respiratory: Cough (2% to 10%), dyspnea (2% to 10%), flu-like symptoms (2% to 10%), rhinitis (2% to 10%)

Miscellaneous: Fever (2% to 10%)

Chronic migraines:

Cardiovascular: Hypertension (2%)

Central nervous system: Headache (5%), exacerbation of migraine headache (4%), facial paresis (2%)

Local: Pain at injection site (3%)

Neuromuscular & skeletal: Neck pain (9%), myasthenia (4%), stiffness (4%), musculoskeletal pain (3%), myalgia (3%), muscle spasm (2%)

Ophthalmic: Blepharoptosis (4%)

Respiratory: Bronchitis (3%)

Lower limb spasticity:

Dermatologic: Excoriation of skin (children and adolescents: 2%)

Gastrointestinal: Decreased appetite (children and adolescents: 2%)

Local: Erythema at injection site (children and adolescents: 2%), pain at injection site (2%)

Neuromuscular & skeletal: Arthralgia (3%), back pain (3%), myalgia (2%), sprain (1% to 2%)

Respiratory: Oropharyngeal pain (children and adolescents: 2%), upper respiratory tract infection (2%)

Upper limb spasticity:

Central nervous system: Seizure (children and adolescents: 1% to 5%), fatigue (2% to 3%)

Gastrointestinal: Nausea (2% to 4%), constipation (children and adolescents: 3%)

Local: Pain at injection site (children and adolescents: 3% to 4%)

Neuromuscular & skeletal: Limb pain (5% to 9%), myasthenia (2% to 4%)

Respiratory: Rhinorrhea (children and adolescents: 4%), nasal congestion (children and adolescents: 3%), bronchitis (2% to 3%)

Other indications (blepharospasm, forehead lines, glabellar lines, lateral canthal lines, primary axillary hyperhidrosis, reduction of glabellar lines, strabismus):

Central nervous system: Anxiety (3% to 10%), pain (3% to 10%), headache (9%), facial pain (1%), facial paresis (1%)

Dermatologic: Diaphoresis (3% to 10%; nonaxillary), pruritus (3% to 10%), skin tightness (2%)

Immunologic: Antibody development (2%)

Infection: Infection (3% to 10%)

Local: Bleeding at injection site (3% to 10%), pain at injection site (3% to 10%)

Neuromuscular & skeletal: Back pain (3% to 10%), neck pain (3% to 10%), asthenia (1%)

Ophthalmic: Dry eye syndrome (6%), superficial punctate keratitis (6%), eyelid edema (1%)

Respiratory: Flu-like symptoms (3% to 10%), pharyngitis (3% to 10%)

Miscellaneous: Fever (3% to 10%)

Frequency not defined:

Other indications (blepharospasm, forehead lines, glabellar lines, lateral canthal lines, primary axillary hyperhidrosis, reduction of glabellar lines, strabismus):

Dermatologic: Skin rash

Ophthalmic: Diplopia, ectropion, eye irritation, eyelid entropion, keratitis, lacrimation, lagophthalmos

<1%, postmarketing, and/or case reports: Any indication: Abdominal pain, acute myocardial infarction, alopecia, amyotrophy, anaphylaxis, anorexia, antibody development (neutralizing), aspiration pneumonia, asthma, blurred vision, brachial plexopathy, cardiac arrhythmia, corneal perforation, corneal ulceration, denervation, dermatitis, diarrhea, drug toxicity (botulinum toxin effects), dysarthria, erythema of skin, erythema multiforme, exacerbation of myasthenia gravis, eye infection, focal facial paralysis, hyperhidrosis, hypersensitivity reaction, hypoacusis, hypoesthesia, inflammation at injection site, jaw pain, madarosis of the eyebrow, malaise, muscle twitching (localized), nerve root disorder, paresthesia, peripheral neuropathy, photophobia, pneumonia, psoriasiform eruption, reduced blinking, respiratory depression, respiratory failure, retinal vein occlusion, retrobulbar hemorrhage, serum sickness, syncope, tinnitus, urinary incontinence, urticaria, vertigo, visual disturbance, voice disorder, vomiting

Warnings/Precautions

Concerns related to adverse effects:

• Anaphylaxis/hypersensitivity reactions: Serious and/or immediate hypersensitivity reactions (eg, anaphylaxis, serum sickness, urticaria, soft tissue edema, dyspnea) have occurred. If a reaction occurs, discontinue and institute immediate treatment.
• Antibody formation: Higher doses or more frequent administration may result in neutralizing antibody formation and loss of efficacy.
• Autonomic dysreflexia: Autonomic dysreflexia has been observed with use and may occur in patients receiving intradetrusor injections for detrusor overactivity associated with a neurologic condition. Clinical presentation often includes headache, a marked increase in blood pressure, and diaphoresis; prompt treatment may be required in patients presenting with severe symptoms (eg, hypertensive crisis) (Furlan 2013).
• Cardiovascular events: Arrhythmia and myocardial infarction (some fatal) have been reported following administration. Some of these patients had risk factors including preexisting cardiovascular disease. The exact relationship to onabotulinumtoxinA has not been established.
• Dysphagia: Common when used for cervical dystonia and may persist for several months after administration. In severe cases (some fatal), patients may require alternative feeding methods (eg, feeding tube). Risk factors include smaller neck muscle mass, bilateral injections into the sternocleidomastoid muscle, or injections into the levator scapulae. Risk of aspiration resulting from severe dysphagia is increased in patients when swallowing is already compromised. Limiting the dose injected into the sternocleidomastoid muscle may reduce the occurrence of dysphagia.
• Hematologic: Use with caution in patients with bleeding disorders and/or receiving anticoagulation therapy.
• Ophthalmic effects: Dry eye, irritation, ocular pain, photophobia, and visual changes have been reported with injection in or near the orbicularis oculi muscle; if symptoms persist, consider ophthalmologic referral.
• Respiratory effects: Bronchitis and upper respiratory infection have been reported more frequently in adults treated for upper or lower limb spasticity.
• Systemic toxicity: [US Boxed Warning]: Distant spread of botulinum toxin beyond the site of injection has been reported; dysphagia and breathing difficulties have occurred and may be life threatening; there have been reports of death; other symptoms reported include asthenia, blurred vision, diplopia, dysarthria, dysphonia, generalized muscle weakness, ptosis, and urinary incontinence, which may develop within hours or weeks following injection. The risk is likely greatest in children treated for spasticity, but symptoms can also occur in adults treated for spasticity and other conditions and particularly in those patients who have an underlying condition that would predispose them to these symptoms. Systemic effects have occurred following use in approved and unapproved uses, including doses comparable to or lower than doses used to treat cervical dystonia and spasticity. Immediate medical attention required if respiratory disorders, speech, or swallowing difficulties appear.
• Urinary retention: An increased incidence of urinary retention and need for catheterization has been observed in patients receiving therapy for bladder dysfunction (overactive bladder or detrusor overactivity associated with a neurologic condition); due to the risk of urinary retention, treatment should only be used in patients able and willing to initiate post-treatment catheterization, if required. Patients with diabetes had an increased incidence of urinary retention. Patients experiencing difficulty in voiding should be instructed to consult their health care provider.
• Urinary tract infection: Therapy in patients with overactive bladder increases the incidence of urinary tract infections (UTIs); clinical trials for overactive bladder excluded patients with >2 UTIs in the previous 6 months and those taking chronic antibiotics for prophylaxis of recurrent UTIs. Consider risks versus benefits when contemplating use in these patients or patients experiencing recurrent UTIs during treatment. Patients with diabetes had an increased incidence of UTI.

Disease-related concerns:

• Episodic migraines: Safety and efficacy have not been established in patients with ≤14 headaches per month.
• Neuromuscular disease: Use with caution in patients with peripheral motor neuropathic diseases, amyotrophic lateral sclerosis, or neuromuscular junction disorders (eg, myasthenia gravis, Lambert-Eaton syndrome). Risk of adverse events including generalized muscle weakness, diplopia, ptosis, dysphonia, dysarthria, severe dysphagia, and respiratory compromise may be increased.
• Ocular diseases: Reduced blinking from injection in or near the orbicularis oculi muscle can lead to corneal exposure, persistent corneal epithelial defect, and ulceration when treating blepharospasm. Retrobulbar hemorrhages may occur from needle penetration into orbit when treating strabismus; spatial disorientation, double vision, or past-pointing may occur if one or more extraocular muscles are paralyzed. Covering the affected eye may help. Careful testing of corneal sensation, avoidance of lower lid injections, and treatment of corneal epithelial defects are necessary. Use caution in patients with angle closure glaucoma.
• Respiratory disease: Use extreme caution in patients with preexisting respiratory disease; treatment with botulinum toxin may weaken accessory muscles that are necessary for these patients to maintain adequate ventilation. Serious breathing difficulties, including respiratory failure, have been reported. Risk of aspiration resulting from severe dysphagia is increased in patients with decreased respiratory function.

Concurrent drug therapy issues:

• Neuromuscular transmission: Use with extreme caution in patients receiving other agents that may interfere with neuromuscular transmission (eg, aminoglycosides, neuromuscular-blocking agents)

Dosage form specific issues:

• Albumin: Product may contain albumin; albumin carries an extremely remote risk for transmission of viral diseases, Creutzfeldt-Jakob disease (CJD) and variant CJD (vCJD). No cases of transmission of viral diseases, CJD, or vCJD have been identified for licensed albumin or albumin contained in other licensed products.
• Product interchangeability: Botulinum products (abobotulinumtoxinA, onabotulinumtoxinA, rimabotulinumtoxinB) are not interchangeable; potency units are specific to each preparation and cannot be compared or converted to any other botulinum product.

Other warnings/precautions:

• Bladder dysfunction: Appropriate use: Rule out acute UTI prior to treatment; appropriate prophylactic antimicrobial therapy is required prior to, during, and following treatment. Discontinue antiplatelet therapy at least 3 days prior to administration.
• Hazardous tasks: May impair ability to drive and/or operate machinery due to the intended effects of treatment; if loss of strength, muscle weakness, or impaired vision occurs, patients should avoid driving or engaging in other hazardous activities.
• Injection site: Use with caution if there is inflammation or excessive weakness or atrophy at the proposed injection site(s); use is contraindicated if infection is present. Serious events (including fatalities) have been observed with direct injection into the esophagus, stomach, salivary glands, and oro-lingual-pharyngeal region. Use caution when administering in close proximity to the lungs (especially the apices); pneumothorax has been reported following administration near the thorax.
• Primary axillary hyperhidrosis: Appropriate use: Evaluate for secondary causes prior to treatment (eg, hyperthyroidism). Safety and efficacy for treatment of hyperhidrosis in other areas of the body have not been established.
• Temporary reduction in glabellar lines: Appropriate use: Do not use more frequently than every 3 months (Canadian labeling states not to use more frequently than every 2 months). Patients with marked facial asymmetry, ptosis, excessive dermatochalasis, deep dermal scarring, thick sebaceous skin, or the inability to substantially lessen glabellar lines by physically spreading them apart were excluded from clinical trials. Use with caution in patients with surgical alterations to the facial anatomy. Reduced blinking from injection of the orbicularis muscle can lead to corneal exposure and ulceration. Spatial disorientation, double vision, or past pointing may occur if one or more extraocular muscles are paralyzed.
• Unapproved use: Serious adverse reactions, including excessive weakness, dysphagia, and aspiration pneumonia, including fatalities, have been reported in patients who have received injections for unapproved uses. In these cases, the reactions were not necessarily related to distant spread of toxin but may have resulted from administration to the site of injection and/or adjacent structures; several patients had preexisting dysphagia or other significant disabilities.
• Upper or lower limb spasticity: Appropriate use: Safety and effectiveness of other upper or lower limb muscle groups have not been established in adults. Treatment has not been shown to improve upper extremity functional abilities or range of motion at a joint affected by a fixed contracture in adults.

Monitoring Parameters

Detrusor overactivity associated with neurologic condition: Evaluate postvoid residual (PVR) urine volume within 2 weeks post-treatment and periodically thereafter up to 12 weeks in patients not catheterizing. Initiate catheterization with PVR urine volume >200 mL and continue until PVR <200 mL.

Pregnancy

Pregnancy Considerations

Information related to the use of onabotulinumtoxinA in pregnancy is limited to case reports for the treatment of cervical dystonia (Aranda 2012; Bodkin 2005; Krug 2015; Newman 2004), achalasia (Holliday 2016; Hooft 2015; Neubert 2019; Wataganara 2009), and migraine (Robinson 2014). In addition, case reports collected by the manufacturer include pregnancy outcome information following use for cosmetic procedures, movement disorders, pain disorders, and hyperhidrosis (Brin 2016).

Because information related to the use of onabotulinumtoxinA in pregnancy is limited, use for indications, such as cervical dystonia and cosmetic procedures, is not recommended (Contarino 2017; Trivedi 2017).

Patient Education

What is this drug used for?

• It is used to lower the number of lines and wrinkles of the face and neck.
• It is used to lower underarm sweating.
• It is used to prevent migraine headaches.
• It is used to treat muscle problems around the eye.
• It is used to treat muscle problems that lead to spasms.
• It is used to treat spasms of the neck.
• It is used to treat an overactive bladder.
• It is used to treat bladder spasms.

Frequently reported side effects of this drug

• Injection site irritation
• Neck pain
• Headache
• Reduced blinking
• Dry eyes
• Cough
• Back pain
• Runny nose
• Flu-like symptoms
• Nausea
• Fatigue
• Common cold symptoms
• Dry mouth

Other side effects of this drug: Talk with your doctor right away if you have any of these signs of:

• Loss of strength and energy
• Blurred vision
• Change in voice
• Infection
• Difficulty breathing
• Difficulty swallowing
• Difficulty speaking
• Vision changes
• Eye pain
• Drooping eyelids
• Drooping eyebrows
• Severe eye irritation
• Dizziness
• Passing out
• Seizures
• Urinary tract infection like blood in the urine, burning or painful urination, passing a lot of urine, fever, lower abdominal pain, or pelvic pain
• Leaking of urine
• Unable to pass urine
• Double vision
• Signs of a significant reaction like wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat.

Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.

Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.