Therapeutic Use of Botulinum Neurotoxins in Dermatology: Systematic Review

Study on botulinum toxin in dermatology from 2000 to 2023: A CiteSpace-based bibliometric analyses

OBJECTIVE

Using bibliometric methods, this study analyzed and summarized the current situation and development of the global application of botulinum toxin in dermatology.

METHODS

Literature published in the Web of Science Core Collection database from January 1, 2000 to October 28, 2023 was searched for topics such as "Botulinum toxin," "Dermatology," and so forth. The number of publications, countries, institutions, journals, authors, cited literature, keywords, and so forth, were analyzed and a visual knowledge map was created using scientometric tools such as CiteSpace, VOSviewer, and Scimago Graphica.

RESULTS

A total of 2039 documents were retrieved and 1877 documents were included after de-duplication and transformation. The country with the highest number of published periodical articles was the United States; the main research institution was Yonsei University; the author with the highest number of published periodical articles was Kim, Hee Jin; and the high-frequency keywords mainly related to indications, combination therapy, and safety optimization.

CONCLUSION

The results of this study provide information on the current status and trends in clinical studies of botulinum toxin in dermatology, which will help researchers identify hotspots and explore new research directions in this field.

Assessing the efficacy and quality of Life improvements of botulinum toxin type a with topical minoxidil versus topical minoxidil in male androgenetic alopecia: a randomized controlled trial

Androgenetic alopecia (AGA) is a common type of hair loss in men and efficacy and safety of current medical treatment remain limited. Therefore, the present study aimed to investigate the efficacy and safety of botulinum toxin type A (BTA) combined with Minoxidil in patients with AGA. 60 male patients were included in this study and control group received topical 5% Minoxidil and the treatment group received BTA combined with topical 5% Minoxidil. BTA injections (60-70 U) were administered at 30-35 scalp sites. Head photographs were taken at baseline, 2nd, 4th, and 6th months. Clinical descriptions recorded scalp conditions, and patient satisfaction along with Dermatology Life Quality Index scores were documented. The treatment group (TG) showed significant hair growth differences compared to the control group (CG) at the 4th month (P < 0.001) and 6th month (P = 0.0046) post-treatment. TG had improved Investigator Global Assessment (IGA) scores in the 4th month (P = 0.0001) and 6th month (P = 0.0259) compared to CG. Patient satisfaction in TG for hair growth and scalp improvement was higher than CG (all P < 0.05). TG exhibited substantial quality of life improvement at the 4-month (P = 0.0009) and 6-month (P = 0.0099). No adverse reactions were observed post-botulinum toxin injection. BTA combined with Minoxidil effectively promotes hair growth, enhances the quality of life, and alleviates scalp symptoms in male AGA patients at 4th and 6th months, with no adverse effects compared to Minoxidil alone.Trial registration number: Ethics Committee of Shanghai Tongji Hospital (ID: K-2018-026).

Treatment of Primary Axillary Hyperhidrosis with Two Doses of Botulinum Toxin A-Observational Study

Hyperhidrosis (HH) is defined as the production of more sweat than is necessary for its thermoregulatory function, negatively affecting patients' quality of life and interfering with their social, work and family life. In this context, the aim of thisstudy was to evaluate the efficacy of two different doses of botulinum toxin type A (50 or 100 units) in each axilla in severe primary axillary hyperhidrosis. A descriptive, observational, cross-sectional and post-authorisation study was conducted onpatients referred to our department.Thirty-one patients with severe primary axillary hyperhidrosis were included, some of whom received more than one infiltration during the follow-up period, performing a total of 82 procedures. They were assigned by simple random sampling to two types of treatment: infiltration of 50 or 100 units (U) of botulinum toxin A per axilla.Hyperhidrosis severity was assessed using the Hyperhidrosis Disease Severity Scale (HDSS), and quality of life was assessed using the Dermatology Life Quality Index (DLQI) questionnaire. Onabotulinum toxin A infiltration reduced the severity of hyperhidrosis and improved the quality of life of the treated patients, with no significant differences between the two groups.

Recent Developments in Engineering Non-Paralytic Botulinum Molecules for Therapeutic Applications

This review discusses the expanding application of botulinum neurotoxin in treating neurological conditions. The article specifically explores novel approaches to using non-paralytic botulinum molecules. These new molecules, such as BiTox or el-iBoNT, offer an alternative for patients who face limitations in using paralytic forms of botulinum neurotoxin due to concerns about muscle function loss. We highlight the research findings that confirm not only the effectiveness of these molecules but also their reduced paralytic effect. We also discuss a potential cause for the diminished paralytic action of these molecules, specifically changes in the spatial parameters of the new botulinum molecules. In summary, this article reviews the current research that enhances our understanding of the application of new botulinum neurotoxins in the context of common conditions and suggests new avenues for developing more efficient molecules.

Pain Control during the Treatment of Primary Palmar Hyperhidrosis with Botulinum Toxin A by a Topical Application of Liposomal Lidocaine: Clinical Effectiveness

Primary palmar hyperhidrosis (PPH) constitutes a debilitating condition that profoundly impacts the social, functional, and occupational aspects of individuals. The intradermal administration of botulinum toxin type A (BoNT-A) stands as an established therapeutic approach for PPH, albeit one frequently accompanied by considerable pain, posing challenges for patient tolerance. Our study aimed to assess the efficacy of combining cryoanalgesia spray (CA) with topical anesthesia utilizing a cream containing liposomal lidocaine at a concentration of 40 mg/g, with the objective of mitigating the pain associated with intradermal BoNT-A injection for PPH treatment. Nineteen participants, aged ≥18 years and afflicted with severe PPH, were enrolled in a double-blind randomized vehicle-controlled trial. Patient-perceived pain during the procedure was quantified using the Numeric Rating Scale (NRS). Statistical analysis was applied to the collected data. The combination of CA and the topical application of liposomal lidocaine during BoNT-A treatment for PPH resulted in diminished pain compared to CA alone and the combination of CA with the application of a basic cream. Topical anesthesia through the application of a liposomal lidocaine-containing cream emerged as a facile, secure, and efficacious approach for alleviating the pain associated with intradermal BoNT-A injection in PPH treatment. Furthermore, it demonstrated compatibility with CA, thereby offering a comprehensive strategy for pain management during BoNT-A administration.

Assessing Botulinum Toxin Effectiveness and Quality of Life in Axillary Hyperhidrosis: A One-Year Prospective Study

This study hypothesized that botulinum toxin (Botox) therapy would sustainably reduce sweat production in axillary hyperhidrosis patients over one year and significantly improve various quality-of-life aspects, including psychological well-being, social interactions, and daily functioning. The objectives were to quantitatively measure changes in sweat production and qualitatively assess the evolving impact on patients' quality of life over one year. Conducted prospectively at the Pius Brinzeu Clinical Emergency Hospital in Timisoara, Romania, this study complied with ethical standards and included adults with primary axillary hyperhidrosis unresponsive to conventional treatments. Participants underwent Botox injections and were evaluated at baseline, six months, and one year, using the Hyperhidrosis Disease Severity Scale (HDSS), WHOQOL-BREF, and the Dermatology Life Quality Index (DLQI), among other tools. Involving 81 patients, the study showed significant improvements in sweat production and quality-of-life metrics. Sweat production decreased from 0.81 g to 0.23 g per 15 min over one year (p < 0.001). HDSS scores reduced from 3.4 to 1.5, indicating a decrease in symptom severity (p < 0.001). The DLQI total score, assessing life quality impact, notably dropped from 19.9 to 6.9 (p < 0.001). Quality-of-life domains also showed significant improvements, especially in the social (from 65.3 to 73.4, p < 0.001) and environmental aspects (from 68.0 to 72.1, p < 0.001). Higher HDSS and sweat production were significantly associated with a lower quality of life on the DLQI (B coefficients of -4.1 and -2.5, respectively). Botulinum toxin therapy proved effective in reducing sweat production and improving the quality of life in axillary hyperhidrosis patients over a one-year period. These improvements were statistically significant in both physical and psychosocial domains. The study highlights the potential long-term benefits of Botox therapy for hyperhidrosis.

Efficacy and Safety Analysis of Botox Application and Iatrogenic Botulism: Panacea or Peril?

Clostridium botulinum toxin-A (BoNT-A) creates temporary paralysis in the muscles by acting on the muscle-nerve junction. It is injected into the mimic muscles when a decrease in the movements of the mimic muscles is desired. Despite many favorable applications, the use of BoNT-A is not without drawbacks. Although there is no expected serious side effect on health in BoNT-A treatments, various problems can be encountered in patients treated for aesthetic purposes. Botulism is a rare but potentially life-threatening syndrome, which is caused by the toxin produced by the bacterium Clostridium botulinum, which acts on the nervous system, vegetative forms of C. botulinum can only survive in anaerobic conditions, while spore forms are common in nature and can withstand harsh conditions. Botulism can stem from bacterial spores which release toxin in the body; in the form of enteric botulism, and wound botulism. The cases that develop 'iatrogenic botulism' after such procedures are usually those receiving high-dose toxin for therapeutic purposes. The treatment of botulism mainly consists of anti-toxin therapy and, if necessary, intensive care to prevent organ failures, including respiratory support. This article aims to cover all these issues related to botulism and other adverse outcomes related to BoNT-A injection in light of the most recent literature.

Botulinum toxin A dissolving microneedles for hyperhidrosis treatment: design, formulation and in vivo evaluation

Multiple periodic injections of botulinum toxin A (BTX-A) are the standard treatment of hyperhidrosis which causes excessive sweating. However, BTX-A injections can create problems, including incorrect and painful injections, the risk of drug entry into the bloodstream, the need for medical expertise, and waste disposal problems. New drug delivery systems can substantially reduce these problems. Transdermal delivery is an effective alternative to conventional BTX-A injections. However, BTX-A's large molecular size and susceptibility to degradation complicate transdermal delivery. Dissolving microneedle patches (DMNPs) encapsulated with BTX-A (BTX-A/DMNPs) are a promising solution that can penetrate the dermis painlessly and provide localized translocation of BTX-A. In this study, using high-precision 3D laser lithography and subsequent molding, DMNPs were prepared based on a combination of biocompatible polyvinylpyrrolidone and hyaluronic acid polymers to deliver BTX-A with ultra-sharp needle tips of 1.5 ± 0.5 µm. Mechanical, morphological and histological assessments of the prepared DMNPs were performed to optimize their physicochemical properties. Furthermore, the BTX-A release and diffusion kinetics across the skin layers were investigated. A COMSOL simulation was conducted to study the diffusion process. The primary stability analysis reported significant stability for three months. Finally, the functionality of the BTX-A/DMNPs for the suppression of sweat glands was confirmed on the hyperhidrosis mouse footpad, which drastically reduced sweat gland activity. The results demonstrate that these engineered DMNPs can be an effective, painless, inexpensive alternative to hypodermic injections when treating hyperhidrosis.

A Retrospective Review of Laser Therapy for Treatment of Hidradenitis Suppurativa

PURPOSE

Hidradenitis suppurativa (HS) is a chronic inflammatory disease characterized by painful and foul-smelling cystic nodules and sinus tracts in the apocrine gland-bearing regions. The treatment options include topical, intralesional, systemic, and surgical modalities. Currently, the most novel therapy is laser therapy to provide localized treatment without systemic adverse effects. However, data regarding patient outcomes after laser treatment are limited because of the low prevalence of this disease. This study aimed to evaluate the efficacy of laser therapy as a treatment modality for patients with HS.

METHODS

A retrospective review cohort analysis of patients with HS undergoing laser treatment between 2016 and 2021 was conducted. Patient demographics, lesion location(s), Hurley stage, age of onset and diagnosis, treatment length, type, outcomes, and complications were analyzed.

RESULTS

Ninety-four patients met the inclusion criteria; on average, patients were treated with 5.8 laser sessions for 14.8 months with no complications and minor blood loss. Hidradenitis suppurativa progression commonly starts during puberty, with a median onset of 13.8 years and diagnosis of HS at 16.2 years. All patients (n = 94) showed an improvement in HS disease severity: 59.6% completed treatment, 12.0% are currently undergoing treatment, and 26.0% were lost to follow-up.

CONCLUSIONS

Laser therapy is an effective and safe therapy for HS leading to improved quality of life and should be considered in the treatment and management of HS.

The Efficacy and Safety of Botulinum Toxin A for the Treatment of Rosacea: A Systematic Review

The off-label use of botulinum toxin type-A (BoNT-A) in treating rosacea seems encouraging, but the evidence is still lacking regarding its efficacy and safety. This study was conducted to summarize the evidence regarding the efficacy and safety of BoNT-A in the treatment of rosacea patients. A comprehensive literature search was conducted in several databases, and 17 studies were included. Before-after and split-face comparisons showed that BoNT-A significantly alleviated the symptoms of facial erythema and flushing and improved the patient's quality of life/satisfaction. However, the symptoms recurred three to six months post-injection, requiring repeated treatments in some patients. The pooled rates of post-injection localized erythema, ecchymosis, and facial muscle affection represented 24.6%, 5.1%, and 4.3%, respectively. BoNT-A seems to be effective in alleviating the symptoms of rosacea with a low rate of adverse events. However, the recurrence of the symptoms a few months after the injection requires repeated sessions, which may raise cost-effectiveness issues. Large-scale clinical trials are required to confirm the effectiveness and define the optimal dosing regimen and the rate of recurrence. Future studies should allow for an adequate follow-up after the treatment, with repeated measurements of the outcomes.

Neuromodulators for Skin

Neurotoxins are the most popular nonsurgical aesthetic procedure for men and women of all ages. Five botulinum toxin A (BoNTA) products represent the current palette of available BoNTA for cosmetic use. Off-label uses of BoNTA continue to expand and are now used for skin rejuvenation, to treat various skin disorders, and in facial nerve paralysis. Dermal and subdermal injections of dilute BoNTA has grown in popularity and been shown to improve skin texture and quality. Common targets for chemodenervation in facial nerve synkinesis are ipsilateral orbicularis oculi, mentalis, depressor anguli oris, buccinator, corrugator muscles, and the ipsilateral and/or contralateral frontalis.

Botulinum neurotoxins: Future innovations

Botulinum neurotoxins (BoNTs) are multi-domain proteins whose potent and selective actions on nerve endings have led to innovations in both basic and clinical science. The various BoNT domains are responsible for binding to gangliosides and proteins associated with nerve cell membranes, internalization into the cell, and cleavage of one or more SNARE (soluble N-ethylmaleimide sensitive factor attachment protein receptor) proteins necessary for vesicle docking and fusion. Novel modifications to BoNT molecules, such as the creation of chimeras, helped identify the protein domains responsible for various aspects of BoNT action, such as localized effects. Other molecular modifications have been introduced in attempts to increase the specificity of BoNTs for autonomic or sensory neurons, with the ultimate goal of optimizing therapeutic selectivity. This research, in turn, has led to the development of BoNT-based proteins that can target non-SNARE substrates such as phosphatase and tensin homolog (PTEN). Still others are developing different BoNT serotypes, subtypes, or variants that are longer- or shorter-acting or have faster onset for various clinical purposes. New formulations of BoNTs that provide convenience for both patients and physicians are under investigation. Novel clinical uses are being evaluated for onabotulinumtoxinA, including in the prevention of post-operative atrial fibrillation. All these innovations capitalize on the unique properties of BoNTs, which continue to intrigue scientists and clinicians across numerous fields of study.

Subjective and Objective Measurements of the Facial Effects of Microdoses of Botulinum Toxin

INTRODUCTION

Studies have suggested that botulinum toxin A may improve skin quality, and application protocols using hyper-diluted doses of botulinum toxin (microdosing) have been studied as a way to achieve therapeutic goals without fully paralyzing the targeted muscles.

OBJECTIVES

To evaluate the effects of a combined protocol utilizing both the standard dosing and the microdosing of AbobotulinumtoxinA for the improvement of skin quality, measured by objective and subjective measurements.

METHODS

Thirty patients were treated with botulinum toxin using both the standard technique and the microdosing technique. Objective (Sebumeter®, Mexameter® and digital dermoscopy pictures) and subjective (Global Aesthetic Improvement Scale and a clinical scale for evaluating the quality of facial skin) measurements of the effects in the treated areas were taken to assess the efficacy of the treatment.

RESULTS

Digital dermoscopy showed a marked reduction of erythema and telangiectasias. Erythema and telangiectasias improved both on objective and subjective measurements. Skin oleosity, static rhytids, papules and pustules and enlarged pores improved on subjective measurements. Patient satisfaction was high (93%) despite the high rate of adverse events (56%).

CONCLUSIONS

The combined application of standard doses and microdoses of AbobotulinumtoxinA is effective in improving the overall quality of facial skin. The effects on erythema and telangiectasias suggest that it is an effective treatment option for patients with erythematotelangiectatic rosacea. When applying microdoses of botulinum toxin in the lower and mid-face, the doses and pattern of injection should be customized for each patient to reduce the occurrence of adverse events.

Botulinum neurotoxin: A therapeutic powerhouse with broad clinical implications

ABSTRACT

Clostridium botulinum is a Gram-positive bacterium that produces one of the most deadly chemodenervating toxins in the world. To date, six distinct neurotoxins are available for prescription use in the United States. Decades of data across aesthetic therapeutic areas and therapeutic disease states support the safety and efficacy of C. botulinum, providing good symptom management and improved quality of life in appropriately chosen patients. Unfortunately, many clinicians are slow to progress patients to toxin therapy from more conservative measures, and others wrongly interchange the products despite characteristics unique to each. Commensurate with an improved understanding of the complex pharmacology and clinical implications of botulinum neurotoxins is the importance for clinicians to appropriately identify, educate, refer, and/or treat candidate patients. This article provides an overview of the history, mechanism of action, differentiation, indications, and uses for botulinum neurotoxins.

Efficacy and Safety of Botulinum Toxin B in Focal Hyperhidrosis: A Narrative Review

Botulinum toxin type B (BoNT-B), known as Myobloc® in the United States and as Neurobloc® in Europe, is a new therapeutically available serotype among the botulinum toxin family. During the last years several data have been reported in literature investigating its efficacy and safety, as well as defining the dosing and application regiments of BoNT-B in the treatment of hyperhidrosis. Moreover, recent studies have been examining its safety profile, which may be different from those known about BoNT-A. The aim of this review is to provide information about what is currently known about BoNT-B in regards to the treatment of focal hyperhidrosis.

The clinical effect of botulinum toxin on pigmentation

BACKGROUND

Botulinum toxin injection is a common cosmetic procedure often used to treat dynamic wrinkles, but it has also been observed to have a lightening effect on the skin. It is thought that this lightening effect develops due to muscle innervation blockage; however, the change in the amount of melanin levels has not been quantified.

METHOD

Thirty-one patients who presented to the dermatology clinic of a tertiary hospital for botulinum toxin injection for wrinkle treatment were included in the study. A standard dose of botulinum toxin was injected to each patient's forehead, glabellar, and crow's feet region, and then the melanin index (MI) was measured with the Mexameter® MX 18 (Courage + Khazaka Electronic, Köln).

RESULTS

After botulinum toxin treatment, a statistically significant decrease was found in the forehead and upper face MI. The upper face total baseline MI was significantly lower in the Glogau 1 group than in the Glogau 2 group (P = 0.033). The forehead 15th day MI was significantly lower in the Glogau 1 group than in the Glogau 2, 3, and 4 groups (P = 0.030).

DISCUSSION

Botulinum toxin application to healthy skin for wrinkle treatment can cause facial skin lightening by reducing MI. It was also remarkable that this decrease was more pronounced in the forehead, which is a region that is particularly vulnerable to sun exposure, compared to other regions. Younger people, who are included in the Glogau type 1 group, may benefit more from this lightening effect.

Neurotoxins Acting at Synaptic Sites: A Brief Review on Mechanisms and Clinical Applications

Neurotoxins generally inhibit or promote the release of neurotransmitters or bind to receptors that are located in the pre- or post-synaptic membranes, thereby affecting physiological functions of synapses and affecting biological processes. With more and more research on the toxins of various origins, many neurotoxins are now widely used in clinical treatment and have demonstrated good therapeutic outcomes. This review summarizes the structural properties and potential pharmacological effects of neurotoxins acting on different components of the synapse, as well as their important clinical applications, thus could be a useful reference for researchers and clinicians in the study of neurotoxins.

A Double-Blind, Split-Face, Randomized Study on the Effects and Safety of Intradermal Injection of Botulinum Toxin A (Incobotulinum Toxin A) in the Cheek

BACKGROUND

Intradermal injection of botulinum toxin A (BTXA) is used for cosmetic purposes without strong evidence for clinical use, as opposed to intramuscular injection.

OBJECTIVE

To evaluate the efficacy and safety of intradermal injection of incobotulinum toxin A (iBTXA) in the cheeks.

METHODS

We conducted a study with 18 volunteers who received intradermal injection of iBTXA into one cheek and normal saline into the contralateral side as a control. Volunteers visited the clinic at weeks 2, 4, 8, and 12 after injection. At each visit, pores and wrinkles were evaluated by a facial analyzer, sebum secretion by a sebumeter, skin texture by both volunteers and clinicians, and wrinkles of the nasolabial fold were graded with photographic reviews.

RESULTS

There were no significant effects on the wrinkles of the infraorbital area and sebum secretion. However, there were significant improvements in the wrinkles of the nasolabial fold and skin texture on the iBTXA injected side. The effects on the wrinkles of the nasolabial fold lasted 12 weeks, and those on skin texture lasted 8 weeks. Improvement in the pore size was observed only at week 2. No serious adverse events were reported except one volunteer who complained of facial palsy after the injection of 30 units of iBTXA in one cheek. However, injection of 20 units of iBTXA in one cheek was not associated with any adverse events.

CONCLUSION

Intradermal injection of iBTXA, could provide clinical benefits for skin texture and wrinkles overcoming the skin prick effect without obvious side effects.

Expert Opinion on Non-Surgical Eyebrow Lifting and Shaping Procedures

Eyebrow elevation and reshaping are common concerns that we handle in everyday practice, and we have noticed that the trend is shifting from a medical concern to a cosmetic one. Several eyebrow lift methods are available, both invasive and non-surgical. The method of choice depends on several factors, such as patient expectations and beliefs, financial budget, acceptance of downtime and the available tools in the practice. In this article, we review the recent literature on non-surgical eyebrow lift methods to provide an overview of the current state of this field. We discuss seven different methods for eyebrow lift and reshaping, including botulinum toxin, dermal fillers, fractional radiofrequency, high-intensity focused ultrasound, thermo-mechanical ablation, lasers, and threads. Moreover, we provide practical insight into the procedure, injection techniques, expected results, and patient satisfaction rate.

How Does Botulinum Toxin Inhibit Itch?

Two decades after reports of the anti-pruritic effects of botulinum neurotoxins (BoNTs), there is still no approved product for the anti-itch indication of BoNTs, and most clinical case reports still focus on the off-label use of BoNTs for various itchy conditions. Few randomized clinical trials have been conducted with controversial results, and the beneficial effects of BoNTs against itch are mainly based on case studies and case series. These studies are valuable in presenting the potential application of BoNTs in chronic pruritic conditions, but due to the nature of these studies, they are categorized as providing lower levels of evidence or lower grades of recommendation. To obtain approval for the anti-pruritic indication of BoNTs, higher levels of evidence are required, which can be achieved through conducting large-scale and well-designed studies with proper control groups and established careful and reliable primary and secondary outcomes. In addition to clinical evidence, presenting the mechanism-based antipruritic action of BoNTs can potentially strengthen, accelerate, and facilitate the current efforts towards further investments in accelerating the field towards the potential approval of BoNTs for itchy conditions. This review, therefore, aimed to provide the state-of-the-art mechanisms underlying the anti-itch effect of BoNTs from basic studies that resemble various clinical conditions with itch as a hallmark. Evidence of the neuronal, glial, and immune modulatory actions of BoNTs in reducing the transmission of itch are presented, and future potential directions are outlined.

Botulinum Toxin Use for Modulating Neuroimmune Cutaneous Activity in Psoriasis

Psoriasis is a complex immune-mediated inflammatory disorder that generates enormous interest within the scientific communities worldwide, with new therapeutic targets being constantly identified and tested. Despite the numerous topical and systemic medications available for the treatment of psoriasis, alternative therapies are still needed for the optimal management of some patients who present with localized, resistant lesions. Novel insights into the contribution of cutaneous neurogenic inflammation in the pathogenesis of psoriasis have yielded exciting new potential roles of nerve-targeting treatments, namely botulinum toxin type A (BoNT-A), for the management of this disease. This paper aims to review the existing literature on knowledge regarding the potential role of BoNT-A in psoriasis treatment, with a focus on its ability to interfere with the immunopathogenetic aspects of psoriatic disease. Furthermore, in our paper, we are also including the first report of psoriatic lesions remission following local BoNT-A injections that were administered for treating upper limb spasticity, in a patient that concomitantly suffered from psoriasis and post-stroke spasticity.

THE PHARMACOLOGICAL TREATMENT AND MANAGEMENT OF HYPERHIDROSIS

INTRODUCTION

Idiopathichyperhidrosis is a dysfunctional disorder involving eccrine sweat glands and its impact on patients' daily quality of life is well-known. Unlike some years ago, when only poor effective and safe therapeutic alternatives were available, nowadays, several emerging pharmacological active substances have gained significant space as treatment options.

AREAS COVERED

The authors report on, in this narrative review, the emerging data from the literature focusing on the pharmacological treatments to draw up a drug treatments flow-chart for patients with idiopathic hyperhidrosis, taking into consideration specific differences among axillary, palmoplantar and craniofacial hyperhidrosis.

EXPERT OPINION

Idiopathic hyperhidrosis, regardless of the site of involvement, remains a functional disorder that places a significant burden on patients. After balancing efficacy against adverse events, systemic therapy, although off-label for all forms of hyperhidrosis can represent an additive therapeutic option for patients with insufficient response to topical treatment according to a step wise therapeutic approach. Until the pathophysiological mechanisms underlying hyperhidrosis are clear, and the etiological therapeutic approach become realistic, the greatest challenge in the therapeutic management of hyperhidrotic patients seems to be the search for the most convenient combination between different therapeutic modalities (topical and systemic agents, and botulinum toxins) to achieve long-term control of the disease symptoms.

Botulinum Toxin Type A for Treatment of Forehead Hyperhidrosis: Multicenter Clinical Experience and Review from Literature

Among the forms of idiopathic hyperhidrosis, those involving the forehead have the greatest impact on patients’ quality of life, as symptoms are not very controllable and are difficult to mask for patients. Although the local injection therapy with Incobotulinum toxin type A (IncoBTX-A therapy) can be considered a rational treatment, data from the literature describing both efficacy and safety of the treatment over the long term are poor. The aim of this report is to describe the single-center experience of five patients seeking treatment, for forehead hyperhidrosis with IncoBTX-A. To evaluate the benefits, safety profile and duration of anhidrosis, patients were treated following a standardized procedure and then followed until clinical relapse. The amount of sweating was measured by gravimetric testing, the extension of hyperhidrosis area was measured through Minor’s iodine starch test, and response to the treatment was evaluated using the Hyperhidrosis Disease Severity Scale (HDSS) and the Dermatology Life Quality Index (DLQI). In all treated patients, a significant anhidrotic effect was observed 4 weeks after the treatment and lasted for approximately 36 weeks. The reduction in sweat production was associated with significant amelioration of symptoms and quality of life for all treated patients. No serious side effects occurred; one patient complained of a mild transient bilateral ptosis. Although further wider studies are required, our preliminary results seem to encourage the use of IncoBTX-A in forehead hyperhidrosis.

Off-Label Use of Botulinum Toxin in Dermatology—Current State of the Art

Botulinum toxin (BoNT) is a neurotoxin produced by the Clostridium botulinum bacteria. Among seven different isoforms, only BoNT-A and BoNT-B are commercially used. Currently, botulinum toxin has been indicated by the U.S. Food and Drug Administration in several disorders, among others: chronic migraine, hyperhidrosis, urinary incontinence from detrusor overactivity, or cosmetics. However, there are numerous promising reports based on off-label BTX usage, indicating its potential effectiveness in other diseases, which remains unknown to many. Among them, dermatological conditions, such as rosacea, annal fissure, Raynaud phenomenon, hypertrophic scars and keloids, and also hidradenitis suppurativa, are currently being investigated. This article aims to provide a comprehensive update on the off-label use of botulinum toxin in dermatology, based on an analysis and summary of the published literature.

Complementary Strategies to Promote Hair Regrowth in Post-COVID-19 Telogen Effluvium

Post-COVID-19 telogen effluvium has been largely reported as a sequela in the post-acute phase of COVID-19, causing major emotional distress among the affected patients. The affected individuals are further exposed to a vast amount of misinformation from the internet and social media and it is important for physicians to be familiar with the phenomenon and provide appropriate counselling to their patients regarding this condition. This article aims to review the evidence-based complementary strategies that can help enhance hair regrowth after post-COVID-19 hair loss, from psychological support and patient education to the importance of optimal nutrition and potential indications and benefits of oral nutritional supplementation, as well as the role of both topical and injectable hair growth stimulators.

Toxicology and pharmacology of botulinum and tetanus neurotoxins: an update

Tetanus and botulinum neurotoxins cause the neuroparalytic syndromes of tetanus and botulism, respectively, by delivering inside different types of neurons, metalloproteases specifically cleaving the SNARE proteins that are essential for the release of neurotransmitters. Research on their mechanism of action is intensively carried out in order to devise improved therapies based on antibodies and chemical drugs. Recently, major results have been obtained with human monoclonal antibodies and with single chain antibodies that have allowed one to neutralize the metalloprotease activity of botulinum neurotoxin type A1 inside neurons. In addition, a method has been devised to induce a rapid molecular evolution of the metalloprotease domain of botulinum neurotoxin followed by selection driven to re-target the metalloprotease activity versus novel targets with respect to the SNARE proteins. At the same time, an intense and wide spectrum clinical research on novel therapeutics based on botulinum neurotoxins is carried out, which are also reviewed here.

Advances in the Treatment of Systemic Sclerosis

Although systemic sclerosis (SSc) is currently incurable, there have been recent advances in treatment. This review article begins by providing a brief background to SSc in terms of disease subtyping and autoantibodies, because both predict disease trajectory and help clinicians to select appropriate monitoring and treatment protocols. Broad principles of management are then described: ‘disease-modifying’ therapies and therapies directed at reducing disease burden and/or progression of SSc-related digital vascular disease and of internal organ involvement. Next, advances in the management of digital vasculopathy, pulmonary arterial hypertension (PAH), interstitial lung disease (ILD) and early diffuse cutaneous SSc are discussed in turn, for example: (a) increased use of phosphodiesterase inhibitors and endothelin receptor antagonists for digital vasculopathy; (b) early recognition and treatment of PAH, including with combination therapies; (c) increased use of mycophenolate mofetil and of nintedanib in ILD; and (d) immunosuppression now as standard practice in early diffuse cutaneous SSc, and autologous haematopoietic stem cell transplantation for highly selected patients with progressive diffuse disease. Finally, future challenges are discussed, including ensuring that all patients with SSc are monitored and treated according to best practice guidelines, and whenever possible giving patients the opportunity to participate in clinical trials.

Raynaud's phenomenon and digital ulcers: advances in evaluation and management

PURPOSE OF REVIEW

The aim of this review is to give an update on advances in evaluation and management of systemic sclerosis (SSc)-related Raynaud's phenomenon and digital ulceration, focusing on reports from the last 18 months. The increasing recognition of the huge impact of Raynaud's phenomenon and of digital ulceration on the everyday lives of patients with SSc has sparked enthusiasm internationally to develop better outcome measures and better treatments, and so a review is timely.

RECENT FINDINGS

There have been recent advances in the development of patient reported outcome instruments [e.g. the Hand Disability in Systemic Sclerosis-Digital Ulcers (HDISS-DU) instrument] and also in noninvasive imaging techniques, including thermography and laser Doppler methods. Improved outcome measures will facilitate future clinical trials, both early phase proof-of-concept and later phase trials. New insights have been gained into mechanisms of action and methods of administration of 'conventional' therapies, for example phosphodiesterase inhibitors and intravenous prostanoids. New treatment approaches are being investigated, including topical and procedural therapies.

SUMMARY

Clinicians can look forward to seeing these advances translating into clinical benefit over the next 5 years. To help ensure this, they should strive whenever possible to recruit patients with SSc-related digital vasculopathy into observational studies and clinical trials.