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Botulinum Toxin Adverse Events

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Provisional chapter
Botulinum Toxin Adverse Events
Raffaela Pero, Sonia Laneri and Giovanna Fico
Additional information is available at the end of the chapter
© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons
Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use,
distribution, and reproduction in any medium, provided the original work is properly cited.
RaaelaPero, SoniaLaneri and GiovannaFico
Additional information is available at the end of the chapter
Abstract
Botulinum toxin acts at the neuromuscular junction (motor plaque) blocking the release
and eects of acetylcholine (ACh), a neurotransmier of both the central nervous system
(CNS) and the peripheral nervous system (SNP). By inhibiting the release of acetylcholine,
botulinum toxin interferes with the nervous impulse and causes a characteristic accid
paralysis of the muscles. This eect is used to decrease wrinkles of the facial skin and chin
providing a smooth appearance and for the treatment of a variety of human syndromes
characterized by hyperfunction of selected nerve terminals. Side eects of this treatment
are rare, but are essentially related to the active ingredient of the drug or to medical mal-
practice. These adverse events and their possible therapy are discussed in this chapter.
Keywords: botulinum toxin, adverse events, therapy, esthetic, motor endplate
1. Introduction
Botulinum toxin is a neurotoxic protein produced by the anaerobic bacterium Clostridium
botulinum. There are seven types of distinct botulinum toxin and are indicated with the alpha-
bet leers: A, B, C, D, E, F, and G [1].
Recently, a novel botulinum neurotoxin (BoNT/X) has been identied [2] and the rst botuli-
num-like toxin outside the Clostridia family has been described [3].
The currently used in esthetic medicine is botulinum toxin type A (BoNT-A). It is used for
wrinkles of expression and for those dynamic wrinkles linked to the hypertonia of mimic
muscles [4]. Botulinum toxin acts at the level of the neuromuscular junction (motor end-
plate) blocking the release and eects of acetylcholine, an ester of acetic acid and choline,
responsible for neurotransmission both at the central nervous system (CNS) level and at the
© 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative
Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use,
distribution, and reproduction in any medium, provided the original work is properly cited.
peripheral nervous system (SNP) level. The enzyme acetylcholineesterase, present in the pre-
synaptic nerve endings, continuously hydrolyses the acetylcholine which is then immediately
resynthesized and stored through an active transport mechanism by means of a specic car-
rier protein, within synaptic cholinergic vesicles of storage. Within these cytosolic vesicles,
acetylcholine is transported to the presynaptic region of the neuron (synaptic buon) where it
waits for the ionic signal (calcium ions) to release its role as a neurotransmier [1].
Acetylcholine is normally released into the synaptic space trough a potential action that, by fol-
lowing the axon of the neuron at the last termination level of the nal arborization of the axon,
determines the opening of voltage-dependent ion channels: the channels of calcium. The cal-
cium ions, present in the synaptic space, penetrate inside the synaptic buon and start the real-
izing process of ACh into the synaptic space where it acts on specic receptors (ACh receptors).
ACh receptors are located on the postsynaptic cell membrane of the muscle brocell, which are
of two types: nicotinic and muscarinic. Interacting with ACh receptors, the neurotransmier
achieves its eects by determining, at the postsynaptic level, the opening of sodium-potassium
ion channels through which the sodium ions penetrate into the muscle brocell which, thus, ini-
tiate muscle contraction. Immediately afterward, ACh is hydrolyzed by acetylcholinesterase. By
inhibiting the release of acetylcholine, botulinum toxin interferes with the nervous impulse and
causes a accid paralysis of the muscles. Botulinum toxin is in fact a real muscle relaxant [4].
Botulin toxin is a double-chain polypeptide consisting of a heavy chain and a light chain. The
former has a molecular weight of 100 KDa while the laer has a molecular weight of 50 KDa.
The heavy chain is linked to the light chain via sulde bridges. The two chains perform dier-
ent functions. The heavy chain binds to a receptor on the cell membrane of the synaptic buon,
the SV2 receptor, and begins the endocytosis phenomenon through which the botulinum toxin
enters into the synaptic buon. The heavy chain works like a sort of light chain conveyor [5].
Once penetrated into the synaptic buon, the botulinum toxin releases the light chain that
can perform its protease function capable of hydrolyzing the proteins of the SNARE complex
(SNAP-25, syntaxin, synaptobrevin) of the neuromuscular junction preventing the release of
ACh from synaptic vesicles [6].
The proteins of the SNARE complex play a crucial role in the release of ACh, because they
favor the fusion between the membrane of the synaptic vesicles in which the acetylcholine
and the membrane of the synaptic buon are stored. The protein that is hydrolyzed is SNAP-
25, and in this way, the fusion between the synaptic vesicle membrane in which the acetyl-
choline and the synaptic membrane are crammed is made impossible, and it is for this reason
that the acetylcholine cannot be released into the synaptic space of the motor plate and the
characteristic accid paralysis of the treated muscles is determined [7].
In 1980, botulin toxin was rst described and used by ophthalmologists in humans for the
treatment of strabismus [8], while its esthetic use was rst reported in 1992 by Carruthers and
Carruthers [9].
1.1. Commercial products of botulinum toxin
The most widespread toxin in the world has the trade name of Botox. Botox for esthetic use
are called:
Botulinum Toxin2
Vistabel® 50 U (corresponding to Botox® used in pathology); the storage of the solution
requires a temperature between 2 and 8°C, because the toxin is thermolabile. According to
the technical sheet, it is maintained for up to 4 hours. According to some scientic works,
in 12 hours, the eect is reduced to 50%. According to other works, the eect remains intact
for 6 weeks. When inserting the needle into the bole, the syringe must be sucked: this is
a sort of test to verify that the product is actually under vacuum and has therefore been
stored correctly;
Azzalure® 125 U (corresponding to the Dysport® used in pathology); and
• Bocouture® 50 U (corresponding to Xeomin® used in pathology) is a bare toxin (not a com-
plex protein like the previous ones). Units are not equivalent. The conversion rate is 2.5 (1 U
Vistabel or Bocouture = 2.5 U Azzalure). Bocouture not requires the cold chain; it is stored
at room temperature (0–25°) for 3 years and presents less risk of allergies as albumin is
absent in the commercial preparation [10].
1.2. Therapeutic uses of BTX
In the last 20 years, the therapeutic spectrum of botulinum toxin has greatly increased.
BoNT-A has been used for a wide range of established and emerging applications grouped
into the following categories:
neurological,
otolaryngological,
ophthalmological,
urological disorders,
esthetic,
gastrointestinal/proctological disorders,
pain, and
symptomatic treatment of Parkinson’s disease (PD) [1113].
1.3. Esthetic uses of BoNT-A
In 2002, AIFA authorized the esthetic use of BoNT-A with the following indication: “Temporary
improvement of vertical wrinkles, moderate to severe, between eyebrows to wrinkling, in adults
aged <65 years, when the severity of such wrinkles has an important psychological impact on
the patient.” Although this is the only indication for esthetic use approved by the regulatory
authority, many physicians use the toxin in o-label mode at injection sites other than those
approved, in particular for periocular and frontal wrinkles [14]. Actually, botulinum toxin is
approved by the US Food and Drug Administration (FDA) for esthetic use in the treatment of:
axillary hyperhidrosis,
glabellar lines, and
lateral canthal lines.
Botulinum Toxin Adverse Events 3
The dynamic rhytides of the upper third of the face are the best indication of botulinum toxin
[15, 16].
These dynamic wrinkles depend on both the muscle factor and the photoaging. If the muscle
factor (young subject) predominates and if the skin is ne, you can hope for a good result;
if photoaging is predominant (older subject) and if the skin is thick, the result is less good.
Despite the apparent ease of injections, the correction of these glabellar wrinkles in particular
requires a good understanding of the anatomy and function of the fur muscles of the region.
It is necessary to respect the depression/elevator balance, which is not the same for each face,
and the type of frowning to choose the appropriate doses and to respect the recommended
injection points (Figure 1) [17].
2. Adverse eve nts
Side eects are essentially related to active ingredient of the drug and are referred to both
therapeutic and esthetic use.
2.1. Eects related to the drug
Regarding the side eects related to the drug, those most frequently reported are:
injection of high doses of this drug (more than 200 units in every injection); and
booster within less than 1 month is dangerous [18].
Side eects of this treatment are rare, but can include bruising, headache, allergic reactions
due to allergy to human albumin or sodium chloride present as an excipient in the drug, facial
and palpebral edema, injection site pain, eye pain, erythema, psoriasis, skin infections, vertigo,
nausea, fever, blepharitis, xerostomia, respiratory virosis, itching, asthenia, muscle weakness,
psychiatric disorders, and pneumonia ab ingestis ineectiveness of the drug (the formation of
antibodies against botulinum toxin neutralizes the eect of the toxin itself).
Figure 1. Fronto-orbital balance of the eyebrows: levator muscles and depressor muscles. The fronto-orbital balance
claries botulinum toxin action: relaxing of the frontalis muscle determines a strength increase of depressor muscles,
with possible ptosis. Instead, relaxing of the depressor muscles causes a strength increase of the frontalis.
Botulinum Toxin4
Botulinum Toxin Adverse Events 5
A scleral show, greater evidence of sclera, can be veried after a functional decit of the eye’s
orbicularis (pars inferior) following interference with the function of this muscle.
Ectropion, anomalous reversal toward the outside of the lower eyelid, is due to functional decit
of the orbicularis muscle of the eye (pars inferior) for chemodenervation of the orbicularis muscle.
A strabismus, deviation of the visual axes, is caused by the malfunction of the extrinsic ocu-
lomotor muscles (lateral rectus) with consequent inability of binocular representation at the
retinal level.
Diplopia is caused by the involvement of the lateral rectus muscle through the diusion of
the toxin inside of the secondary orbitary cavity with inoculation too deep and close to the
margin orbital. Temporary monolateral ocular bandage may be useful (Figure 3) [27–29].
Smile asymmetry is due to the toxin diusion into the nearby zygomaticus major muscle and
asymmetry of mouth mobility is caused by the blockage of the zygomatic muscle with ptosis
of the lip (Figure 4).
Diculty in whistling occurs after a functional decit of the orbicular muscle of the mouth.
Incidence may be reduced using diluted doses of botulinum toxin [30, 31].
Figure 2. Schematic representation of eyelid ptosis complication of BoNT-A administration: uilateral eyelid ptosis.
Botulinum Toxin6
Botulinum toxin is often interesting to mitigate the fold of the marionee, which gives the face
a sad and aged appearance, injecting the depressor of the corner of the mouth, which lowers
the labial commissures. The injection must be low to prevent the lips from spreading to the
orbicularis [32].
At the neck, the araction through the posterior platysmal cords of the area in which the
falling cheeks are delineated can be aenuated by the Nefertiti lift, injecting two or three
small doses along the posterior platysmal chord and the mandibular edge. The anterior and
posterior platysmal chords can be mitigated by small doses of botulinum toxin, injected every
2 cm, pinching and aracting the rope forward [33, 34].
All of these events resolved spontaneously maybe dose-dependent and were aributed to
local diusion of BoNT into adjacent areas [35].
Serious adverse events related to the cosmetic use of botulinum toxin include thyroid eye
disease in a patient with Graves hyperthyroidism, sarcoidal granuloma, pseudoaneurysm of
the frontal branch of the superior temporal artery, and respiratory damage [36–39].
2.3. Side eects of therapeutic use
Recent studies demonstrate that BoNT tracking is not restricted to the neuromuscular junc-
tion, but also involves internalization of the toxin by spinal cord motor neurons and fast
axonal retrograde transportation. Toxin’s eect is sometimes observed beyond the site of local
injection. Major adverse events can include:
Figure 3. Schematic representation of diplopia complication of BoNT-A.
Botulinum Toxin Adverse Events 7
death,
anaphylaxis,
dysphagia,
respiratory insuciency, and
muscle weakness.
These systemic events are rare and observed only at high dosages or in patients with underly-
ing medical conditions predisposing to the complications [40–44].
Bahtia et al. reported on three patients in whom treatment of their dystonia with therapeutic
doses of botulinum toxin resulted in clinical muscle weakness distant from the site of injec-
tions. It may be speculated that repeated injections at intervals of 10–12 weeks as in their
patients may have an impact on toxin binding and diusion. In fact, according to authors, the
cause is most likely presynaptic inhibition due to systemic spread of the toxin [45]. Even in the
case of repeated blepharospasm treatments with BoNT-A, an induction of acute myasthenic
crisis has been demonstrated [46].
Figure 4. Schematic representation of asymmetry of mouth mobility of BoNT-A administration.
Botulinum Toxin8
Systemic adverse events have been reported at the time of botulinum toxin A injection
(6% injection episodes) and at follow-up (22% injection episodes) in children with cerebral
palsy (CP), and children in Gross Motor Function Classication System (GMFCS) levels IV
and V have increased rates of systemic adverse events [47].
Tugnoli et al. describes a rst case of generalized muscular weakness associated with signs of
systemic cholinergic autonomic impairment who was treated with 1400 U of BoNT-A for axil-
lary and palmar hyperhidrosis. The authors assert that this case is consistent with a mild but dif-
fuse Botulism-like syndrome, probably related to the high BoNT-A doses uses and to numerous
intradermal injections and the slight build of their patient [48].
All these data demonstrate the possible risk of unwanted adverse eects due to spreading of
the toxin [42].
2.4. Diusion and migration of BoNT
In the diusion phenomena, the concentration gradient and the BoNT molecular size deter-
mine the movement of the toxin beyond the immediate injection site through Brownian
motion even if these muscles are separated by fasciae. In migration instead, a haematic and
neuroaxonal transport of BoNT occurs, which is distant from the muscle and is related to
systemic side eects that may be fatal if left untreated [49, 50].
Experimental studies in rodents have shown that botulinum toxin receptors exist in the cen-
tral nervous system and a small amount of botulinum toxin crosses the blood-brain barrier.
This raises the possibility that botulinum toxin is transported retrogradely, similar to tetanus
toxin, and may cause centrally mediated side eects [51].
Botulinum toxin type-A can induce autonomic eects such as biliary colic, impairment of
gastrointestinal and cardiovascular autonomic pathways, and inhibition of autonomic cholin-
ergic pathways in the bladder. Cholinergic receptors in the pharyngeal and laryngeal sphinc-
ters are likely to be inhibited by systemic spread of BoNT and may be the main reason for
dysphagia/dysphonia [52–54].
One of the suggested mechanisms for transport of the toxin from one part of the body (neck) to
a remote location (toes) is the vascular spread via absorption through the capillary system and
the retrograde axonal spread of the toxin. The injection of proximal upper extremity muscles
with BoNT-A can determine diusion of the toxin into the surrounding muscles resulting in
dysphagia. These data suggest a systemic spread even when toxin is injected in sites anatomi-
cally adjacent to the locus of the side eect. Retrograde axoplasmic spread of the toxin is the
second possible mechanism for the observed distant adverse events.
Recent studies show retrograde transport of enzymatically active toxin molecules via micro-
tubules in the axon to both sensory and motor regions in the spinal cord after intramuscular
and intraneural injections of BoNT-A. In fact, antinociceptive eect of BoNT-A may occur
through retrograde spread of BoNT-A from the sensory nerves in the periphery to the central
nervous system. Moreover, distant eects also may be caused by intrafusal uptake of the toxin
in the muscles spindles as well as neuroplastic changes post-BoNT-A injections. Diusion of
BoNT is aected by a variety of factors; however, dose, concentration, and volume probably
are the greatest contributors that increase the risk of diusion. In general, the BoNT reduction
in amplitude increased with increasing doses and with increasing concentration [55–57].
Botulinum Toxin Adverse Events 9
To limit diusion is target muscle localization using EMG and endoscopic or imaging guidance
[58].
2.5. Nonresponsiveness to treatment with BoNT
Nonresponsiveness to BoNT could be as a result of possible factors that include misdiag-
nosis, insucient dose, problems with toxin storage and preparation, and administration.
Another possible reason for lack of clinical eect is immunoresistance to BoNT, which refers
to ineectiveness of the toxin as a result of development of neutralizing antibodies against
the toxin [59].
The formation of neutralizing antibodies to BoNT is increased by a short time period between
injections, the administration of booster injections, and the use of high BoNT doses. To pre-
vent antibody formation against BoNT, the practitioner can use a newer BoNT formulation
with the lowest protein content [60].
3. Contraindications and interactions with some medications
BoNT is contraindicated in patients with known peripheral motor neuropathies or neuro-
muscular disorders, such as Eaton-Lambert syndrome, multiple sclerosis, and myasthenia
gravis, because further chemodenervation may exacerbate muscle weakness. The cause is to
be found in a reduced release of acetylcholine in the neuromuscular endplate, due to the eect
of autoantibodies against the presynaptic channels of calcium [61].
The treatment can be performed in the 18–65 age range. Other contraindications are represented
by:
allergy to human albumin and/or sodium chloride,
skin infections,
presence of scleral show,
senile ectropion,
pregnancy,
lactation,
dysphagia, and
psychiatric disorders.
Aminoglycoside antibiotics that can enhance the eect of botulinum toxin are netilmicin,
tobramycin, gentamicin, neomycin, amikacin, kanamycin, and streptomycin. Other drugs that
also interfere with neuromuscular transmission are muscle relaxants such as D-tubocurarine,
baclofen, thiocolchicoside, tizanidine, diazepam, dantrolene, and pridinol [62, 63].
Botulinum Toxin10
4. Rehabilitation of the motor endplate
The rehabilitation of the motor endplate can be very useful in case of side eects following
treatment with botulinum toxin.
Radioiodinated botulinum toxin A (125I-BoNT/A-complex, 67 or 344 U free-125I-BoNT/A)
was injected into the gastrocnemius muscle of rats and measured in various tissues at dier-
ent time points. These “in vivo” studies allowed to establish that after 24 hours, the toxin is no
longer present in the inltrated muscle.
Thus, the side eects reported seem to be related to the damage caused by toxin caused and
not to the presence of it in the muscles. These eects can be visible after 10–12 days [64].
For this reason, it is useless to administer the antitoxin which exerts its action by binding to
the toxin still in circulation, complexing it and making it inactive. Furthermore, the healing
capacity depends on the regeneration of the aected synaptic terminations.
Because the light chain of botulinum toxin causes proteolysis of the SNAP 25 protein, reduc-
ing its endocellular pool, one must reestablish its own physiological endocellular pool.
In practice, it is necessary to stimulate the biosynthesis of the SNAP25 protein to favor the
structural and functional recovery of the motor endplate.
The aim of the therapy is to stimulate the biosynthesis of the SNAP 25 protein, consisting of
about 200 amino acids. So, we can correct side eects such as ectropion, diplopia, palpebral
ptosis, strabismus, scleral show, and asymmetries of smile and mouth mobility.
To improve the biosynthesis of the SNAP 25 protein, it is necessary to take:
a. A proteic diet (meat, sh);
b. Amino acids such as arginine and cysteine as they belong to the molecular composition
of the SNAP-25 protein. Then, we supplement other amino acids: arginine, bioargin, and
cysteine;
c. L-acetylcarnitine which is an agonist of the mitochondrial growth function and reparative
agents (NGF), expounds an antioxidant activity in the neurons of the central and periph-
eral nervous system. L-acetylcarnitine is structurally similar to acetylcholine and plays an
indispensable role for proper cellular energy, metabolism, and neurotransmission;
d. Alpha-lipoic acid (also called thioctic acid), a fat-soluble vitamin that participates in vari-
ous antioxidant mechanisms such as the regeneration of reduced glutathione (GSH) and
ascorbic acid; and
e. L-carnosine, a dipeptide composed of β-alanine and L-histidine; it has the ability to pro-
mote protein regeneration even in dicult situations such as in the late stage of the life
cycle. It has antioxidant properties.
This therapy is able to guarantee fast responses (7–10 days) and in 80% of cases [65–68].
Botulinum Toxin Adverse Events 11
5. Conclusions
The use of BoNts continues to steadily expand and multiply. New indications of clinical use of
BoNTs are continuously emerging in medical therapy and further applications will be devel-
oped in the future. Adverse events occur more frequently after the clinical use of the toxin, but
may also disclose after its esthetic use. The safe utilization of BoNTs requires knowledge of its
indications and pharmacology, anatomy of the treated muscles to avoid serious complications.
Author details
Raaela Pero1*, Sonia Laneri2 and Giovanna Fico3
*Address all correspondence to: pero@unina.it
1 Department of Molecular Medicine and Medical Biotechnology, University of Naples
“Federico II”, Naples, Italy
2 Department of Pharmacy, University of Naples “Federico II”, Naples, Italy
3 ASL Napoli 3 Sud, Naples, Italy
References
[1] Rosseo O, Pirazzini M, Montecucco C. Botulinum neurotoxins: Genetic, structural and
mechanistic insights. Nature Reviews. Microbiology. 2014;12:535-549. DOI: 10.1038/
nrmicro3295
[2] Zhang S, Masuyer G, Zhang J, Shen Y, Lundin D, Henriksson L, Miyashita S-I, Martínez-
Carranza M, Dong M, Stenmark P. Identication and characterization of a novel botulinum
neurotoxin. Nature Communications. 2017;8. DOI: 14130. DOI: 10.1038/s41467-017-01534-z
[3] Zornea I, Azarnia-Tehran D, Arrigoni G, Anniballi F, Bano L, Leka O, Zanoi G, Binz T,
Montecucco C. The rst non Clostridial botulinum-like toxin cleaves VAMP within the
juxtamembrane domain. Scientic Reports. 2016;6:302-357. DOI: 10.1038/srep30257
[4] Pirazzini M, Rosseo O, Eleopra R, Montecucco C. Botulinum neurotoxins: Biology, phar-
macology, and toxicology. Pharmacological Reviews. 2017;69:200-235. DOI: 10.1124/pr.
116.012658
[5] Rummel A. Double receptor anchorage of botulinum neurotoxins accounts for their
exquisite neurospecicity. Current Topics in Microbiology and Immunology. 2013;364:
61e90. DOI: 10.1007/978-3-642-33570-9_4
[6] Pantano S, Montecucco C. The blockade of the neurotransmier releaseapparatus by
botulinum neurotoxins. Cellular and Molecular Life Sciences. 2014;71:793e811. DOI:
10.1007/s00018-013-1380-7
Botulinum Toxin12
[7] Blasi J, Chapman ER, Link E, Binz T, Yamasaki S, De Camilli P, Südhof TC, Niemann H,
Jahn R. Botulinum neurotoxin A selectively cleaves the synaptic protein SNAP-25. Nature.
1993;365:160-163. DOI: 10.1038/365160a0
[8] Sco AB. Botulinum toxin injection into extraocular muscles as an alternative to strabis-
mus surgery. Journal of Pediatric Ophthalmology and Strabismus. 1980;17:21-25
[9] Carruthers JD, Lowe NJ, Menter MA, Gibson J, Eadie N, Botox Glabellar Lines II Study
Group. Double-blind, placebo-controlled study of the safety and ecacy of botulinum
toxin type A for patients with glabellar lines. Plastic and Reconstructive Surgery. 2003 15;
112:1089-1098. DOI: 10.1111/j.1524-4725.2006.32333.x
[10] Albanese A. Clinical guidelines: No more mistaken identities for botulinum neurotox-
ins. Nature Reviews. Neurology. 2016;12:373-374. DOI: 10.1038/nrneurol.2016.86
[11] Erbguth F, Briner W, Fogel W, Hefter H, Herting B, von Lindern JJ, Umstadt HE. Botulinum
toxin in migraine. Journal of Neurology. 2004;251:i31-i32. DOI: 10.1007/s00415-004-1107-7
[12] Erbguth FJ. Historical notes on botulism, Clostridium botulinum, botulinum toxin, and the
idea of the therapeutic use of the toxin. Movement Disorders, the ocial Journal of MDS.
2004;19:S2-S6. DOI: 10.1002/mds.20003
[13] Jankovic J, Brin MF. Botulinum toxin: Historical perspective and potential new indica-
tions. Muscle & Nerve. Supplement. 1997;6:S129-S145
[14] Wu DC, Fabi SG, Goldman MP. Neurotoxins: Current concepts in cosmetic use on the face
and neck-lower face. Plastic and Reconstructive Surgery. 2015;136:76S-79S. DOI: 10.1097/
PRS.0000000000001750
[15] Carruthers J, Fournier N, Kerscher M, Ruiz-Avila J, Trindade de Almeida AR, Kaeuper G.
The convergence ofmedicine and neurotoxine: A focus on botulinum toxin type A and
its application in aesthetic medicine. Part II. Dermatol Dermatologic Surgery. 2013;39:
510-525. DOI: 10.1111/dsu.12148
[16] Raspaldo H, Baspeyras M, Bellity P, Dallara JM, Gassia V, Niforos FR, et al. Upper-
and mid-face anti-aging treatment and prevention using onabotulinumtoxin A: The
2010 multidisciplinary French consensus-part 1. Journal of Cosmetic Dermatology.
2011;10:36-50. DOI: 10.1111/j.1473-2165.2010.00544.x
[17] Trindade De Almeida AR, Secco LC, Carruthers A. Handling botulinum toxins: An
updated literature review. Dermatologic Surgery. 2011;37:1553-1565. DOI: 10.1111/j.
1524-4725.2011.02087.x
[18] Cavallini M, Cirillo P, Fundaro SP, Quartucci S, Sciuto C, Sito G, Tonini D, Trocchi G,
Signorini M. Safety of botulinum toxin A in aesthetic treatments: A systematic review of
clinical studies. Dermatologic Surgery. 2014;40:525-536. DOI: 10.1111/dsu.12463
[19] Jia Z, Lu H, Yang X, Jin X, Wu R, Zhao J, Chen L, Qi Z. Adverse events of botulinum toxin
type A in facial rejuvenation: A systematic review and meta-analysis. Aesthetic Plastic
Surgery. 2016;40:769-777. DOI: 10.1007/s00266-016-0682-1
Botulinum Toxin Adverse Events 13
[20] Cox SE, Adigun CG. Complications of injectable llers and neurotoxins. Dermatologic
Therapy. 2011;24:524-536. DOI: 10.1111/j.1529-8019.2012.01455.x
[21] Hirsch R, Stier M. Complications and their managementin cosmetic dermatology. Der-
matologic Clinics. 2009;27:507-520. DOI: 10.1016/j.det.2009.08.013
[22] Wollina U, Konrad H. Managing adverse events associated with botulinum toxin type A: A
focus on cosmetic procedures. American Journal of Clinical Dermatology. 2005;6:141-150
[23] Klein A. Cosmetic therapy with botulinum toxin: Anecdotalmemoirs. Dermatologic Sur-
gery. 1996;22:757-759
[24] Burns RL. Complications of botulinum exotoxin. 25th Annual Clinical and Scientic
Meeting of the ASDS; Portland,OR; May, 1998
[25] Foster JA, Barnhorst D, Papay F, et al. The use of botulinum A toxin to ameliorate facial
kinetic frown lines. Ophthalmology. 1996;103:618-622
[26] de Almeida AR, Cernea SS. Regarding browlift with botulinum toxin. Dermatologic
Surgery. 2001;27:848
[27] Huang W, Rogachefsky AS, Foster JA. Browlift with botulinum toxin. Dermatologic Sur-
gery. 2000;26:55e60
[28] Lorenc ZP, Smith S, Nestor M, Nelson D, Moradi A. Understanding the functional anat-
omy of the frontalis and glabellar complex for optimal aesthetic botulinum toxin type A
therapy. Aesthetic Plastic Surgery. 2013;37(5):975e983. DOI: 10.1007/s00266-013-0178-1
[29] Carruthers A, Carruthers J. Clinical indications and injection technique for the cosmetic
use of botulinum A exotoxin. Dermatologic Surgery. 1998;24:1189-1194
[30] Garcia A, Fulton JE Jr. Cosmetic denervation of the muscles of facial expression with
botulinum toxin. A dose-response study. Dermatologic Surgery 1996;22:39-43
[31] Lowe NJ, Yamauchi P. Cosmetic uses of botulinum toxins for loweraspects of the face
and neck. Clinics in Dermatology. 2004;22:18e22. DOI: 10.1016/j.clindermatol.2003.12.025
[32] Klein AW. Contraindications and complications with the use of botulinum toxin. Clinics
in Dermatology. 2004;22:66-75. DOI: 10.1016/j.clindermatol.2003.12.026
[33] Dayan SH. Complications from toxins and llers in the dermatology clinic: Recognition,
prevention, and treatment. Facial Plastic Surgery Clinics of North America. 2013;21:
663-673. DOI: 10.1016/j.fsc.2013.07.008
[34] Carruthers J, Carruthers A. Botulinum toxin A in the mid and lower faceand neck.
Dermatologic Clinics. 2004;22:151e158
[35] Geister TL, Blessmann-Gurk B, Rzany B, Harrington L, Gortelmeyer R, Pooth R. Validated
assessment scale for platysmal bands. Dermatologic Surgery. 2013;39:1217e1225. DOI:
10.1111/dsu.12240
[36] Levy PM. The ‘Nefertiti lift’: A new technique for specic re-contouring of the jawline.
Journal of Cosmetic and Laser Therapy: Ocial Publication of the European Society for
Laser Dermatology. 2007;9:249e252. DOI: 10.1080/14764170701545657
Botulinum Toxin14
[37] Eleopra R, Tugnoli V, Caniai L, De Grandis D. Botulinum toxin treatment in the facial
muscles of humans: Evidence of an action in untreated near muscles by peripheral local
diusion. Neurology. 1996;46:1158-1160
[38] Ahbib S, Lachapelle JM, Marot L. Sarcoidal granulomas following injections of botulinum
toxin A (Botox) for corrections of wrinkles. Annales de Dermatologie et de Vénéréologie.
2006;133:43-45
[39] Harrison A, Erickson J. Thyroid eye disease presenting after cosmetic botulinum toxin
injections. Ophthalmic Plastic & Reconstructive Surgery. 2006;22:397-398. DOI: 10.1097/
01.iop.0000231332.24471.27
[40] Prado A, Fuentes P, Guerra C, et al. Pseudoaneurysm of the frontal branch of the super-
cial temporal artery: An unusual complication after the injection of Botox. Plastic and
Reconstructive Surgery. 2007;119:2334-2335. DOI: 10.1097/01.prs.0000261095.07321.09
[41] Nong LB, He WQ, Xu YH, et al. Severe respiratory failure after injection of botulinum
toxin: Case report and review of the literature (in Chinese). Zhonghua Jie He He Hu Xi
Za Zhi. 2008;31:369-371
[42] Cote TR, Mohan AK, Polder JA, Walton MK, Braun MM. Botulinum toxin type A injec-
tions: Adverse events reported to the US Food and Drug Administration in therapeutic
and cosmetic cases. Journal of the American Academy of Dermatology. 2005;53:407-415.
DOI: 10.1016/j.jaad.2005.06.011
[43] Albavera-Hernandez C, Rodriguez JM, Idrovo AJ. Safety of botulinum toxin type A among
children with spasticity secondary to cerebral palsy: A systematic review of randomized
clinical trials. Clinical Rehabilitation. 2009;23:394-407. DOI: 10.1177/0269215508099860
[44] Apkon SD, Cassidy D. Safety considerations in the use of botulinum toxins in children
with cerebral palsy. PM & R. 2010;2:282-284. DOI: 10.1016/j.pmrj.2010.02.006
[45] Bhatia KP, Münchau A, Thompson PD, Houser M, Chauhan VS, Hutchinson M, Shapira AH,
Marsden CD. Generalised muscular weakness after botulinum toxin injections for dystonia:
A report of three cases. Journal of Neurology, Neurosurgery, and Psychiatry. 1999;67:90-93
[46] Beer KR, Wilson F. Skin cooling provides minimal relief of patient discomfort during
periocular botulinum toxin type A injection. Dermatologic Surgery. 2011;37:870-872. DOI:
10.1111/j.1524-4725.2011.01851.x
[47] Swinney CM, Bau K, Burton KLO, O’Flaherty SJ, Bear NL, Paget SP. Severity of cerebral
palsy and likelihood of adverse events after botulinum toxin A injections. Developmental
Medicine and Child Neurology. 2018;60:498-504. DOI: 10.1111/dmcn.1368629451702
[48] Tugnoli V, Eleopra R, Quatrale R, Capone JG, Sensi M, Gastaldo E. Botulism-like syn-
drome after botulinum toxin type A injections for focal hyperhidrosis. The British Journal
of Dermatology. 2002;147:808-809
[49] Halle M. Explanation of timing of botulinum neurotoxin eects, onset and duration, and
clinical ways of inuencing them. Toxicon. 2015;107:64-67. DOI: 10.1016/j.toxicon.2015.07.013
Botulinum Toxin Adverse Events 15
[50] Ramirez-Castaneda J, Jankovic J, Comella C, Dashtipour K, Fernandez HH, Mari Z.
Diusion, spread,and migration of botulinum toxin. Movement Disorders, the Ocial
Journal of MDS. 2013;28:1775-1783. DOI: 10.1002/mds.25582
[51] Currà A, Berardelli A. Do the unintended actionsof botulinum toxin at distant sites have
clinical implications? Neurology. 2009;72:1095-1099. DOI: 10.1212/01.wnl.0000345010.
98495.fc
[52] Schnider P, Brichta A, Schmied M, Au E. Gallbladder dysfunction induced by botulinum
A toxin. Lancet. 1993;342:811-812
[53] Girlanda P, Vita G, Nicolosi C, Milone S, Messina C. Botulinum toxin therapy: Distant eects
on neuromuscular transmission andautonomic nervous system. Journal of Neurology,
Neurosurgery, and Psychiatry. 1992;55:844-845
[54] MacKenzie I, Burnstock G, Dolly JO. The eects of puried botulinum neurotoxin type
A on cholinergic, adrenergic and non-adrenergic, atropine-resistant autonomic neuro-
muscular transmission. Neuroscience. 1982;7:997-1006
[55] Hsu TS, Dover JS, Arndt KA. Eect of volume and concentration on the diusion of
botulinum exotoxin A. Archives of Dermatology. 2004;140:1351-1354. DOI: 10.1001/
archderm.140.11.1351
[56] Borodic GE, Ferrante R, Pearce LB, Smith K. Histologic assessment of dose-related diu-
sion and muscle ber response after therapeutic botulinum A toxin injections. Movement
Disorders. 1994;9:31-39. DOI: 10.1002/mds.870090106
[57] Wohlfarth K, Schwandt I, Wegner F, et al. Biological activity of two botulinum toxin type
A complexes (Dysport and Botox) in volunteers: A double-blind, randomized, dose-rang-
ing study. Journal of Neurology. 2008;255:1932-1939. DOI: 10.1185/03007990903028203
[58] Kinne D. Botulinum toxin A injections in children: Technique and dosing issues. American
Journal of Physical Medicine & Rehabilitation. 2004;83:S59-S64. DOI: 10.1097/01.PHM.
0000141131.66648.E9
[59] Benecke R. Clinical relevance of botulinum toxin immunogenicity. BioDrugs. 2012;26:
e1-e9. DOI: 10.2165/11599840-000000000-00000
[60] Naumann M, Albanese A, Heinen F, et al. Safety and ecacy of botulinum toxin type A
following long-term use. European Journal of Neurology. 2006;35-40(suppl 4):13. DOI:
10.1111/j.1468-1331.2006.01652.x
[61] Adelson RT. Botulinum neurotoxins: Fundamentals for the facial plastic surgeon.
American Journal of Otolaryngology. 2007;28:260-266. DOI: 10.1016/j.amjoto.2006.09.002
[62] Dressler D, Eleopra R. Clinical use of non-A botulinum toxins: Botulinum toxintype
B. Neurotoxicity Research. 2006;9:121-125
[63] Frankel AS, Markarian A. Cosmetic treatments and strategies for the upper face. Facial
Plastic Surgery Clinics of North America. 2007;15:31-39. DOI: 10.1016/j.fsc.2006.11.004
Botulinum Toxin16
[64] Tang-Liu DD, Aoki KR, Dolly JO, de Paiva A, Houchen TL, Chasseaud LF, Webber C.
Intramuscular injection of 125I-botulinum neurotoxin-complex versus 125I-botulinum-
free neurotoxin: Time course of tissue distribution. Toxicon. 2003;42:461-469
[65] Burgoyne RD, Morgan A. Cysteine string protein (CSP) and its role in preventing neuro
degeneration. Seminars in Cell & Developmental Biology. 2015;40:153-159. DOI: 10.1016/
j.semcdb.2015.03.008
[66] Yuji K, Lourdes C, Cyndy, Sandra A, Paula C, Bickford CV. Dietary supplementa-
tions as neuroprotective therapies: Focus on NT-020 diet benets in a rat model of
stroke. International Journal of Molecular Sciences. 2012;13:7424-7444. DOI:10.3390/
ijms13067424
[67] Pongrac JL, Slack PJ, Innis SM. Dietary polyunsaturated fat that is low in (n-3) and high
in (n-6) fay acids alters the SNARE protein complex and nitrosylation in rat hippocam-
pus. The Journal of Nutrition. 2007;137:1852-1856. DOI: 10.1093/jn/137.8.1852
[68] Cunha MP, Pazini FL, Ludka FK, Rosa JM, Oliveira Á, Budni J, Ramos-Hryb AB,
Lieberknecht V, Beio LE, Martín-de-Saavedra MD, López MG, Tasca CI, Rodrigues
AL. The modulation of NMDA receptors and L-arginine/nitric oxide pathway is impli-
cated in the anti-immobility eect of creatine in the tail suspension test. Amino Acids.
2015;47:795-811. DOI: 10.1007/s00726-014-1910-0
Botulinum Toxin Adverse Events 17
... Botulism is a serious paralytic disease [77]. The toxin acts by blocking the release of a neurotransmitter, acetylcholine, at the neuromuscular junction, interfering with the nervous impulse and causing muscle paralysis [78]. ...
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