Use of Botulinum Toxin in Treating Rosacea: A Systematic Review

Treating rosacea with botulism toxin: Protocol for a systematic review and meta-analysis

BACKGROUND

Rosacea is a chronic inflammatory disease usually associated with persistent erythema and periodic flushing. This disease is difficult to treat, and the outcomes are often unsatisfactory and prone to recurrence. In recent years, botulinum toxin has been used as a new treatment for rosacea; however, its efficacy and safety remain under discussion. Although a systematic review of the effectiveness and safety of botulinum toxin has been previously conducted by other researchers, our systematic review and meta-analysis evaluate the efficacy of botulinum toxin from a more comprehensive and detailed perspective to provide evidence for clinicians.

METHODS

Any study using botulinum toxin for the treatment of rosacea was considered for the analysis.

RESULTS

A total of 22 studies were included, 9 of which were randomized controlled trials involving 720 subjects. After treatment, all studies showed varying degrees of improvement in patient signs and symptoms along with reduced Clinician's Erythema Assessment (CEA) scores. The improvement was maintained for several months, and the adverse effects were mild and self-limiting.

CONCLUSION

Botulinum toxin may be an effective treatment for patients with rosacea; however, further clinical evidence is needed to confirm its long-term efficacy and side effects. The study was preregistered with Prospero (CRD42022358911).

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.

Exploring the Pathogenesis and Mechanism-Targeted Treatments of Rosacea: Previous Understanding and Updates

Rosacea is a chronic inflammatory skin disease characterized by recurrent erythema, flushing, telangiectasia, papules, pustules, and phymatous changes in the central area of the face. Patients with this condition often experience a significant negative impact on their quality of life, self-esteem, and overall well-being. Despite its prevalence, the pathogenesis of rosacea is not yet fully understood. Recent research advances are reshaping our understanding of the underlying mechanisms of rosacea, and treatment options based on the pathophysiological perspective hold promise to improve patient outcomes and reduce incidence. In this comprehensive review, we investigate the pathogenesis of rosacea in depth, with a focus on emerging and novel mechanisms, and provide an up-to-date overview of therapeutic strategies that target the diverse pathogenic mechanisms of rosacea. Lastly, we discuss potential future research directions aimed at enhancing our understanding of the condition and developing effective treatments.

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.

Rosacea Aggravated after Intracutaneous Injection of Poly-L-lactic Acid through a Stamp-type Microneedle

Injectable poly-L-lactic acid (PLLA) has been widely used for skin texture improvement, volume augmentations of the face or body, and other cosmetic or reconstructive treatment. Despite its significant efficacy, many side effects have also been reported. Here, we describe a case of rosacea aggravated by intracutaneous injection of PLLA using a mesogun injector with stamp-type microneedle. After the treatment, the patient exhibited aggravated rosacea symptoms, such as flushing and erythema. A possible mechanism for the exacerbations might be that PLLA stimulated subclinical inflammatory reaction in the skin. We suggest that PLLA injection should be administered more cautiously in patients with rosacea or other inflammatory skin lesions.

Botulinum Toxin A Alleviates Persistent Erythema and Flushing in Patients with Erythema Telangiectasia Rosacea

Introduction

The persistent erythema and flushing seen in some cases of rosacea do not respond effectively to, or may easily relapse after, oral medication or light-based therapies (laser or intense pulsed light). Intradermal botulinum toxin A (BTX-A) injection can be used to treat intractable erythema and flushing, but studies with large samples and long-term observation have not been conducted to determine its effectiveness and safety. The aim of this study is thus to investigate the effective duration and safety of intradermal BTX-A injection for intractable erythema and flushing.

Methods

Sixteen patients with rosacea with erythema telangiectasia were injected with BTX-A at 1-cm intervals between each point. Clinician Erythema Assessment (CEA) scores were obtained at baseline and 1 month after injection. Flushing assessment and survey using the Dermatological Quality of Life Index (DLQI) questionnaire were conducted at baseline and at 1, 3, and 6 months after injection.

Results

At 1 month after injection, CEA scores revealed significant improvements in erythema and flushing; the results of the questionnaire on flushing and DLQI indicated that the improvement of flushing usually lasted for 3–6 months, but the effect decreased significantly at 6 months, and individual patients needed another treatment.

Conclusions

BTX-A significantly improves the symptoms and quality of life of patients with refractory rosacea with few adverse effects.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13555-022-00784-0.

Topical calcineurin inhibitors as a double-edged sword in rosacea: A systematic review

BACKGROUND

Rosacea is a chronic inflammatory disease mainly with skin or ocular manifestations. Topical calcineurin inhibitors, pimecrolimus and tacrolimus, can be used to treat rosacea. However, they can also induce rosacea-like eruptions.

AIMS

This study systematically reviewed the double-edged sword effects of pimecrolimus and tacrolimus on rosacea.

METHODS

Four databases were retrieved to search for articles on the effects of pimecrolimus and tacrolimus on rosacea, including Cochrane Library, Embase, PubMed, and Web of Science. Only English articles were included in the systematic review. Relevant data were collected, and the levels of evidence were evaluated.

RESULTS

28 articles published between 2001 and 2016 were included. 11 articles were about pimecrolimus as the treatment of rosacea, 4 articles were about the pimecrolimus-induced rosacea, 9 articles were about tacrolimus as the treatment of rosacea, and 4 articles were about tacrolimus-induced rosacea. Participants for each study ranged from 1 to 200. Several types of outcome measurements were used for these publications.

CONCLUSIONS

Both pimecrolimus and tacrolimus might have double-edged sword effects on rosacea. Pimecrolimus and tacrolimus could be effective for rosacea. However, both of them could also induce rosacea. Larger, randomized, controlled studies on pimecrolimus and tacrolimus as the treatment of rosacea and studies on the mechanisms of pimecrolimus and tacrolimus in treating or inducing rosacea are needed. This systematic review emphasized the double-edged sword role of topical calcineurin inhibitors in rosacea, which may pave the way for future research.