Search Results (25)

Stiff person syndrome (SPS) is an autoimmune disorder with muscle stiffness and spasms, for which current therapies provide incomplete relief. Botulinum neurotoxin (BoNT) has been explored as an adjunctive symptomatic treatment. The aim of this review was to critically evaluate the clinical evidence for BoNT therapy in SPS. Using Medline, Scopus and Google Scholar, we identified nine reports that were published up to 1 January 2026. English articles and articles with information on study type, type/dose of BoNT and treatment results were included. One study was double-blind and placebo-controlled, one was retrospective and seven were single-case reports, comprising 46 patients. Open-label trials used botulinumtoxin-A (Botox, Dysport or Xeomin), while the blind study applied abobotulinumA (Dysport). All but one study (a case report) demonstrated motor improvement and a reduction in painful spasms associated with patient satisfaction. Reported doses ranged from 300 to 800 units for onabotulinumtoxinA and incobotulinumtoxinA and from 700 to 1000 units for abobotulinumtoxinA. The literature highlights the need for randomized clinical trials in larger cohorts, with careful selection of dose, injection sites, and adjunct physiotherapy, as well as an evaluation of early BoNT therapy in SPS. The novelty of this review lies in its critical synthesis of reported data and inclusion of most recent reports. Full article

Notalgia paresthetica is a condition characterized by pruritus and pain in the upper back, often associated with skin discoloration in the same area. Through Medline, Google Scholar, and Scopus search engines, we identified reports of eight clinical studies (published up to 1 December 2025) on the subject of botulinum neurotoxin therapy for Notalgia Paresthetica (NP). Only one of the eight studies was double-blind and placebo-controlled. The search strategy included only articles published in English and Spanish, and articles providing basic information such as the type of study, type and dose of the toxin, and results of the treatment. Articles not in English or Spanish, review articles, and articles failing basic information were excluded. A total of 34 patients were found across all studies. The injected toxin in the open-label studies was onabotulinumtoxin-A (Botox), whereas in the blinded study, the investigators used incobotulinumtoxinA (Xeomin). All open-label studies reported improvement in pruritus, and some reported improvement in pain, whereas the blinded study failed to do so. The possible reasons for this discrepancy between the blinded and the open-label studies are discussed. There is a need for double-blind, placebo-controlled studies with a larger number of patients, preferably using the same neurotoxin that has suggested efficacy in the open-label studies. The novelty of this review is that it represents a comprehensive and critical literature assessment on this topic and that it includes data not present in the previous reviews of this subject. Full article

Background: Cosmetic injection of botulinum neurotoxin type A (BoNT/A) into the submandibular glands is increasingly performed to enhance jawline contour. Although generally considered safe, unintended diffusion of the toxin can impair pharyngeal musculature and lead to dysphagia. Severe aspiration-prone dysphagia after esthetic submandibular gland injection has rarely been described. Case Presentation: A healthy 37-year-old woman developed acute oropharyngeal dysphagia the day after receiving cosmetic contouring injections with incobotulinumtoxinA (Xeomin^®), administered to both submandibular glands (20 units per gland, performed without ultrasound guidance). She presented to our rehabilitation medicine clinic 11 days later with severe difficulty swallowing solids and liquids. Her functional oral intake was severely restricted (Functional Oral Intake Scale [FOIS] score 3), and the Eating Assessment Tool-10 (EAT-10) score was 24. Videofluoroscopic swallowing study (VFSS) demonstrated markedly delayed pharyngeal swallow initiation, reduced palatal elevation, poor airway protection, consistent laryngeal penetration, and silent aspiration of thin liquids (Penetration–Aspiration Scale score 8). She underwent diet modification and structured dysphagia rehabilitation. At three months, repeat VFSS showed substantial improvement, with only occasional penetration of large-volume thin liquids, corresponding to FOIS 5 and EAT-10 score 8. By five months, VFSS confirmed complete resolution of penetration and aspiration with normalization of swallowing physiology, reflected by a FOIS score of 7 and EAT-10 score of 1. Conclusions: This case demonstrates that cosmetic incobotulinumtoxinA injection into the submandibular glands, particularly when performed without ultrasound guidance, can lead to significant oropharyngeal dysphagia. Clinicians performing esthetic lower-face procedures should be aware of this potential complication and ensure timely swallowing evaluation and rehabilitation when symptoms arise. Full article

Using Medline and Scopus as search engines, we identified reports of 10 clinical studies (published up to 1 September 2025) on botulinum neurotoxin therapy for hereditary spastic paraplegia (HSP). Nine studies were conducted in adults and one in children. Only one of the ten studies was double-blind and placebo-controlled. The search strategy included only articles published in English and articles providing basic information such as the type of the study, type and dose of the toxin and results of the treatment. Articles not in English, case reports and review articles were excluded. A total of 258 patients were included across all studies. The injected toxin in the open-label studies was botulinumtoxin-A (Botox or Dysport or Xeomin), whereas in the blinded study, the investigators used Prosigne. All open-label studies, which used FDA approved botulinumtoxin-A neurotoxins, demonstrated a degree of motor and non-motor improvement, whereas treatment with Prosigne did not improve patients’ function. The possible reasons for this discrepancy between the blinded study and the open-label studies are discussed. We found no studies on the effect of BoNTs on bladder dysfunction in HSP. There is a need for double-blind, placebo-controlled studies assessing the efficacy of FDA-approved botulinum neurotoxins in children and adults affected by hereditary spastic paraparesis. Such studies should also investigate the effect(s) of early botulinum neurotoxin therapy in this disorder. The novelty of this review is that it represents a comprehensive and critical literature review on this subject, with no other studies of this kind published previously. It also includes data not present in previous reviews of this subject. Full article

This retrospective study investigates botulinum toxin changes in 206 patients with spasticity, following reimbursement adjustments in France. The main objective was to evaluate the tolerance and efficacy of these changes, a topic underexplored due to the common practice of maintaining the same toxin brand. The majority of patients switched from Botox to Xeomin (73.66%), while others switched from Botox to Dysport (14.63%) or from Xeomin to Dysport (11.71%). Dose adjustments varied depending on the switch, with the change from Botox to Xeomin showing the greatest diversity in adjustments. Overall, tolerance was good, with few adverse effects reported, primarily fatigue. Perceived efficacy fluctuated, with some patients noting improvement while others experienced deterioration, but the median remained stable. A majority of patients (57.06%) chose to continue with their new treatment, indicating general satisfaction, though 42.93% preferred to return to their initial treatment. This study highlights the importance of an individualized approach and careful monitoring during toxin changes. The results suggest that toxin switches can be made without an increase in adverse effects. While differences between groups were observed, they were not statistically significant. Placebo and nocebo effects may influence perceptions of efficacy and side effects during treatment changes. Full article

Botulinum neurotoxin type-A (BoNT/A), which blocks quantal acetylcholine (ACh) release at the neuromuscular junction (NMJ), has demonstrated its efficacy in the symptomatic treatment of blepharospasm. In 3.89% of patients treated for blepharospasm at Tenon Hospital, BoNT/A was no longer effective in relieving the patient’s symptoms, and a partial upper myectomy of the Orbicularis oculi muscle was performed. We used surgical waste samples from 14 patients treated with repeated injections of either abobotulinumtoxinA (Dysport^®) or incobotulinumtoxinA (Xeomin^®). These muscle fragments were compared to others from 4 normal subjects, naïve of BoNT/A. The morphological study was performed blinded to the BoNT/A treatment and between treated and control samples. Neuromuscular specimens analyzed by confocal laser scanning microscopy, using fluorescent staining and immune-labeling of presynaptic proteins, revealed that the pattern of innervation (e.g., polyneuronal and convergent innervation), the muscle nicotinic ACh receptors (nAChRs), and the NMJs exhibited marked differences in BoNT/A-treated muscles (regardless of the toxin clinically used), with respect to controls. BoNT/A-treated junctions exhibited profuse polyneuronal innervation in which 2–6 axons innervated 74.84% of single muscle fibers, while 99.47% of control junctions were mono-innervated. Another new finding was the stable convergent innervation, in which several motor axons end onto the same endplate. Morphological signs of synapse elimination included the presence of retraction bulbs in axons and nerve terminals and a reduced extension of postsynaptic nAChRs. These outcomes suggest that synapse elimination is altered and raise questions on the origin and factors contributing to the plasticity changes observed and the functioning of NMJs. Full article

Background: Approximately 90% of scoliosis cases are adolescent-idiopathic (AIS). From the first appearance of scoliosis at 10–14 years of age until the age of 18, the spine is most vulnerable to deterioration; young, growing people are most susceptible to the worsening of one or more scoliotic curves. An effective non-surgical means of remediation would be welcome. Design: This was a randomized, controlled, two-arm study assessing the safety and efficacy of combining incobotulinum injections with yoga to reverse lumbar and thoracolumbar AIS. Methods: In a private clinic setting, non-pregnant, healthy 12–18 year-olds were either taught a symmetrical “placebo” yoga pose (control sub-group 1), performed the side plank (Vasisthasana) three times daily with a placebo injection (control sub-group 2) or performed the three-times-daily side plank with a botulinum injection (intervention group 3). Injection: For the injection, 33 IU of incobotulinumtoxin type A (Xeomin) was injected into the concave-side lumbar paraspinals and quadratus lumborum at L2–3 and the psoas muscle at L3–4, or participants were injected similarly with a placebo. Randomization was achieved using random.org. Objective: The objective was to determine whether the treatment of muscular asymmetry with botulinum toxin injections and side planks is safe and effective in AIS. Results/Outcome: Eleven intervention and thirteen placebo patients (Groups 1 + 2), who were 12–18 years old, completed the three-month study. Mean daily side plank time = 165 s. The mean initial lumbar curvature was 36.9 degrees (SD 14.36), (p < 0.0001); the mean Group 3 curvature at 3 weeks was 29.5 degrees (SD 14.23) (p < 0.0001); and the mean Group 3 curvature at 3 months was 26.0 degrees (SD 12.81). Onset vs. 3-month value: p < 0.0001. Harms were limited to one patient in Group 2 and one in Group 3, who complained of transient shoulder pain and supported themselves temporarily on their forearm instead of the palm of the extended hand. Conclusion: Muscle strength asymmetry appears to be relevant to AIS treatment. Incobotulinum injections combined with side planks performed with the convex side downward may be more effective in reversing lumbar AIS than placebo exercises or side planks and placebo injections. Full article

Background: Several studies have considered Botulinum Neurotoxin Type A injections effective in treating temporomandibular joint disorder (TMD) symptoms. A double-blind, randomized, controlled clinical trial investigated the benefit of complementary incobotulinumtoxinA (inco-BoNT/A) injections in the masticatory muscles of patients submitted to bilateral temporomandibular joint (TMJ) arthroscopy. Methods: Fifteen patients with TMD and an indication for bilateral TMJ arthroscopy were randomized into inco-BoNT/A (Xeomin, 100 U) or placebo groups (saline solution). Injections were carried out five days before TMJ arthroscopy. The primary outcome variable was a Visual Analogue Scale for TMJ arthralgia, and secondary outcomes were the myalgia degree, maximum mouth opening, and joint clicks. All outcome variables were assessed preoperatively (T0) and postoperatively (T1—week 5; T2—6-month follow-up). Results: At T1, the outcomes in the inco-BoNT/A group were improved, but not significantly more than in the placebo group. At T2, significant improvements in the TMJ arthralgia and myalgia scores were observed in the inco-BoNT/A group compared to the placebo. A higher number of postoperative reinterventions with further TMJ treatments were observed in the placebo group compared to inco-BoNT/A (63% vs. 14%). Conclusions: In patients submitted to TMJ arthroscopy, statistically significant long-term differences were observed between the placebo and inco-BoNT/A groups. Full article

Xeomin^® is a commercial formulation of botulinum neurotoxin type A (BoNT/A) clinically authorized for treating neurological disorders, such as blepharospasm, cervical dystonia, limb spasticity, and sialorrhea. We have previously demonstrated that spinal injection of laboratory purified 150 kDa BoNT/A in paraplegic mice, after undergoing traumatic spinal cord injury (SCI), was able to reduce excitotoxic phenomena, glial scar, inflammation, and the development of neuropathic pain and facilitate regeneration and motor recovery. In the present study, as proof of concept in view of a possible clinical application, we studied the efficacy of Xeomin^® in the same preclinical SCI model in which we highlighted the positive effects of lab-purified BoNT/A. Data comparison shows that Xeomin^® induces similar pharmacological and therapeutic effects, albeit with less efficacy, to lab-purified BoNT/A. This difference, which can be improved by adjusting the dose, can be attributable to the different formulation and pharmacodynamics. Although the mechanism by which Xeomin^® and laboratory purified BoNT/A induce functional improvement in paraplegic mice is still far from being understood, these results open a possible new scenario in treatment of SCI and are a stimulus for further research. Full article

Background: Botulinum toxin type A (BoNT-A) therapy for upper-limb tremor has emerged as a promising option. However, it is unclear in real-world practices whether a technology-guided approach can compare with expert clinical assessments (including surface anatomy and palpation) for improving outcomes. This retrospective study aims to review our clinical outcomes of treating essential tremor (ET) and Parkinson’s disease (PD) tremor using either clinical- or kinematic-based injection pattern determination methods. Methods: 68 ET and 45 PD patients received at least one injection for their upper-limb tremor (unilateral or bilateral) in the last 7 years. Demographics of patients and BoNT-A injections were collected. A Mann–Whitney U statistical test was used to compare outcome measures between ET and PD cohorts. Results: Mean age (72 ± 9 years), number of injections (5), years receiving therapy (~2 years), clinic- (~57%) or kinematic-based patterns, and self-paying (52%) were similar between both cohorts. BoNT-A as a monotherapy in both upper limbs was received in more ET than PD patients. Double reconstitution of Xeomin^® in the wrist flexors/extensors, supinator, biceps, and triceps were most injected. Discontinuation due to no benefit/weakness was not dependent on the injection pattern determination approach. Conclusions: Kinematic-based BoNT-A injections produced similar treatment outcomes to injections based on the clinical expertise of the expert injector. This suggests that kinematics could be used by a non-expert to attain equivalent efficacy potentially improving access to this treatment. Full article

Botulinum neurotoxin type A (BoNT/A) causes muscle paralysis by blocking cholinergic signaling at neuromuscular junctions and is widely used to temporarily correct spasticity-related disorders and deformities. The paralytic effects of BoNT/A are time-limited and require repeated injections at regular intervals to achieve long-term therapeutic benefits. Differences in the level and duration of effectivity among various BoNT/A products can be attributed to their unique manufacturing processes, formulation, and noninterchangeable potency units. Herein, we compared the pharmacodynamics of three BoNT/A formulations, i.e., Botox^® (onabotulinumtoxinA), Xeomin^® (incobotulinumtoxinA), and Coretox^®, following repeated intramuscular (IM) injections in mice. Three IM injections of BoNT/A formulations (12 U/kg per dose), 12-weeks apart, were administered at the right gastrocnemius. Local paresis and chemodenervation efficacy were evaluated over 36 weeks using the digit abduction score (DAS) and compound muscle action potential (CMAP), respectively. One week after administration, all three BoNT/A formulations induced peak DAS and maximal reduction of CMAP amplitudes. Among the three BoNT/A formulations, only Coretox^® afforded a significant increase in paretic effects and chemodenervation with a prolonged duration of action after repeated injections. These findings suggest that Coretox^® may offer a better overall therapeutic performance in clinical settings. Full article

Registered pharmacological treatments are insufficiently effective for erectile dysfunction (ED) in around 30% of affected men. Intracavernosal injection (ICI) of ona- and abobotulinumtoxinA can reduce ED in insufficient responders. We aimed to assess the safety and effectiveness of incobotulinumtoxinA ICI as an add-on therapy to phosphodiesterase-type 5 inhibitors (PDE5-Is) or prostaglandinE1 ICIs (PGE1 ICIs) to treat ED that did not respond sufficiently to this treatment alone. We retrospectively analyzed data from 66 men with difficult to treat ED treated with single or repeated incobotulinumtoxinA 100U ICI as an add-on therapy. Response rate (increase in International Index of Erectile Function-Erectile Function domain score ≥ the minimum clinically important difference) was 52% (median (1st–3rd quartile) 43.5 (34–71) days post-incobotulinumtoxinA ICI). ED etiology (except spinal cord injury) and severity did not influence effectiveness. Only a clinically significant response to the 1st injection predicted a request for a 2nd injection (OR = 5.6, 95%, CI 1.6–19.4). Three men reported mild penile pain during the injection. These results provide preliminary evidence for the effectiveness and safety of incobotulinumtoxinA ICI as an add-on therapy to treat ED that is insufficiently responsive to standard care and provides support for the multicenter randomized clinical trial NCT05196308. Full article

Botulinum neurotoxin type A (BoNT-A) is the active substance in pharmaceutical preparations widely used worldwide for the highly effective treatment of various disorders. Among the three commercial formulations of BoNT-A currently available in Italy for neurological indications, abobotulinum A toxin (Dysport^®, Ipsen SpA, Milano, Italy) and incobotulinum A toxin (Xeomin^®, Merz Pharma Italia srl, Milano, Italy) differ in the content of neurotoxin, non-toxic protein, and excipients. Clinical applications of BoNT-A adopt extremely diluted solutions (10⁻⁶ mg/mL) for injection in the target body district. Near-infrared spectroscopy (NIRS) and chemometrics allow rapid, non-invasive, and non-destructive methods for qualitative and quantitative analysis. No data are available to date on the chemometric analysis of the spectral fingerprints acquired from the diluted commercial formulations of BoNT-A. In this proof-of-concept study, we tested whether NIRS can categorize solutions of incobotulinum A toxin (lacking non-toxic proteins) and abobotulinum A toxin (containing non-toxic proteins). Distinct excipients in the two formulations were also analyzed. We acquired transmittance spectra in the visible and short-wave infrared regions (350–2500 nm) by an ASD FieldSpec 4™ Standard-Res Spectrophotoradiometer, using a submerged dip probe designed to read spectra in transflectance mode from liquid samples. After preliminary spectra pre-processing, principal component analysis was applied to characterize the spectral features of the two BoNT-A solutions and those of the various excipients diluted according to clinical standards. Partial least squares-discriminant analysis was used to implement a classification model able to discriminate the BoNT-A solutions and excipients. NIRS distinguished solutions containing distinct BoNT-A commercial formulations (abobotulinum A toxin vs. incobotulinum A toxin) diluted at recommended volumes for clinical reconstitution, distinct proteins (HSA vs. incobotulinum A toxin), very diluted solutions of simple sugars (lactose vs. sucrose), and saline or water. Predictive models of botulinum toxin formulations were also performed with the highest precision and accuracy. Full article

Under continuous long-term treatment with abo- or onabotulinum toxin type A (BoNT/A), ~10 to 15% of patients with cervical dystonia (CD) will develop neutralizing antibodies and reduced responsiveness over an ~10-year treatment period. Among the botulinum neurotoxin type A preparations so far licensed for CD, incobotulinum toxin A (incoBoNT/A; Xeomin^®) is the only one without complex proteins. Whether CD patients with treatment failure under abo- or onaBoNT/A may still respond to incoBoNT/A is unknown. In this cross-sectional, retrospective study, 64 CD patients with secondary treatment failure after abo- or onaBoNT/A therapy who were switched to incoBoNT/A were compared to 34 CD patients exclusively treated with incoBoNT/A. The initial clinical severity of CD, best outcome during abo- or onaBoNT/A therapy, severity at the time of switching to incoBoNT/A and severity at recruitment, as well as all corresponding doses, were analyzed. Furthermore, the impact of neutralizing antibodies (NABs) on the long-term outcome of incoBoNT/A therapy was evaluated. Patients significantly improved after the switch to incoBoNT/A (p < 0.001) but did not reach the improvement level obtained before the development of partial secondary treatment failure or that of patients who were exclusively treated with incoBoNT/A. No difference between abo- and onaBoNT/A pretreatments or between the long-term outcomes of NAB-positive and NAB-negative patients was found. The present study demonstrates significant long-term improvement after a switch to incoBoNT/A in patients with preceding secondary treatment failure after abo- or onaBoNT/A therapy and confirms the low antigenicity of incoBoNT/A. Full article

There are few reports on the safety and effectiveness of long-term botulinumtoxin A (BoNT A) therapy in severe chronic pain of post-herpetic neuralgia (PHN). The literature was searched with the term “neuropathic pain” and “botulinum” on PubMed (up to 29 February 2020). Pain was assessed with the Visual Analogue Scale (VAS) before and after BoNT A therapy. A total of 10 clinical trials and six case reports including 251 patients with PHN were presented. They showed that BoNT A therapy had significant pain reduction (up to 30–50%) and improvement in quality of life. The effect duration seems to be correlated with BoNT A doses injected per injection site. Intervals between BoNT A injections were 10–14 weeks. No adverse events were reported in cases and clinical studies, even in the two pregnant women, whose babies were healthy. The repeated (≥6 times) intra/subcutaneous injections of incobotulinumtoxin A (Xeomin^®, Merz Pharmaceuticals, Germany) over the two years of our three cases showed marked pain reduction and no adverse events. Adjunctive local BoNT A injection is a promising option for severe PHN, as a safe and effective therapy in long-term management for chronic neuropathic pain. Its effect size and -duration seem to be depended on the dose of BoNT A injected per each point. Full article