GLASS LAB · Medical Aesthetics Evidence Index 303 cells · 19,226 papers · 5,969 top-tier evidence

Wrinkle / Line · Forehead horizontal lines

Botulinum toxin a evidence for Forehead horizontal lines

B 62.1 / 100 Supported 28 RCT/meta · 7 clinical/observational · 9 case · 94 total
Good evidence · positive conclusion

There is a relatively good level of clinical evidence, and a majority of papers support its effectiveness.

Grade combines the quantity and quality of the research, while direction is a separate signal showing how the papers assess effectiveness.

Includes meta-analysis/SR Median year 2019 Last 5 years 39% Positive results 51% Negative results 3 Korea/Asia 4

Known in Korea as

톡신보톡스제오민디스포트코어톡스주름 보톡스다한증 보톡스디자인 보톡스사각턱 보톡스얼굴전체 톡신

Procedure and brand names vary, but the evidence above applies to the same procedure mechanism.

Key papers

tier1 Aesthetic Improvements Over Time: Long-Term Efficacy and Additional Outcomes of IncobotulinumtoxinA in the Simultaneous Treatment of Upper Facial Lines. Journal of cosmetic dermatology · 2025 · PMID 40968493

Abstract summary (English) BACKGROUND/OBJECTIVES: Two Phase III randomized controlled trials were conducted in the US (ULTRA I) and Germany (ULTRA II) to investigate the efficacy of incobotulinumtoxinA for simultaneous treatment of upper facial lines (UFLs: glabellar frown lines [GFLs], horizontal forehead lines [HFLs] and lateral canthal lines [LCLs]). PATIENTS/METHODS: Healthy adults with moderate to severe GFLs, HFLs, and symmetrical LCLs...

Journal Article, Randomized Controlled Trial, Clinical Trial, Phase III, Multicenter Study

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tier1 IncobotulinumtoxinA in the Treatment of Upper Facial Lines: Results From Two Randomized, Double-Blind, Placebo-Controlled, Phase III Studies. Aesthetic surgery journal · 2025 · PMID 39475143

Abstract summary (English) BACKGROUND: Two randomized, double-blind, placebo-controlled, Phase III studies of incobotulinumtoxinA for treating upper facial lines (UFLs; ie, a combination of glabellar frown lines [GFLs], horizontal forehead lines [HFLs], and lateral canthal lines [LCLs]) were conducted in the United States (ULTRA I: NCT04594213) and Germany (ULTRA II: NCT04622254). OBJECTIVES: The aim of this study was to evaluate the safety...

Journal Article, Randomized Controlled Trial, Clinical Trial, Phase III, Multicenter Study

View on PubMed
tier1 Meta-Analysis of Adverse Reactions of Botulinum Toxin A in Facial Rejuvenation Treatment. Aesthetic plastic surgery · 2024 · PMID 39623228

Abstract summary (English) BACKGROUND: Facial rejuvenation is a popular non-surgical treatment, and its treatment safety is of key significance to patients. The purpose of this meta-analysis is to compare the effects of botulinum toxin A and placebo on the occurrence of adverse reactions in facial rejuvenation treatment. OBJECTIVE: According to PRISMA guidelines, a comprehensive search was conducted in Chinese and English databases, and 20...

Journal Article, Meta-Analysis

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tier1 Does Linear or Spot Injection Technique Matter in Upper Face Botulinum Toxin Type A Application? A Split-Face Randomized Trial. Plastic and reconstructive surgery · 2023 · PMID 37184512

Abstract summary (English) BACKGROUND: Although the efficacy of botulinum toxin type A (BoNTA) has been shown to vary depending on injection layer, reconstitution volume, and BoNTA formulation, the effect of injection pattern has rarely been mentioned. The authors compared the therapeutic effects in patients treated with BoNTA with retrograde linear and traditional spot injection techniques. METHODS: Twenty-eight participants were enrolled in...

Journal Article, Randomized Controlled Trial, Comparative Study, Research Support, Non-U.S. Gov't

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tier1 The Efficacy and Duration of Onabotulinum Toxin A in Improving Upper Facial Expression Lines With 64-Unit Dose Optimization: A Systematic Review and Meta-Analysis With Trial Sequential Analysis of the Randomized Controlled Trials. Aesthetic surgery journal · 2023 · PMID 36099476

Abstract summary (English) BACKGROUND: Onabotulinumtoxin A (Onabot A) was the first treatment to be approved for aesthetic indications, namely glabellar lines (GLs), crow's feet lines (CFLs), and forehead lines (FHLs), with a cumulative dose of 64 U. OBJECTIVES: The aim of this study was to conduct a meta-analysis to combine the available data for approved doses for GLs, CFLs, and FHLs to explore the effect and duration of simultaneous...

Meta-Analysis, Systematic Review, Journal Article

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tier1 FollowTheSutures: Piloting a new way to administer onabotulinumtoxinA for chronic migraine. Cephalalgia : an international journal of headache · 2022 · PMID 35166150

Abstract summary (English) BACKGROUND: Anatomical and experimental data indicate that onabotulinimtoxin A could be more efficient and cost-effective for treating chronic migraine with injections targeting the cranial sutures, where collaterals from the meninges penetrate the skull. METHODS: A new injection paradigm (FollowTheSutures) was tested for safety, tolerability and feasibility in a Phase II, open-label, non-controlled, single-center...

Journal Article, Randomized Controlled Trial

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tier1 Onabotulinumtoxin Type A Dosage for Upper Face Expression Lines in Males: A Systematic Review of Current Recommendations. Aesthetic surgery journal · 2021 · PMID 33532814

Abstract summary (English) BACKGROUND: Botulinum toxin injection is the most commonly performed minimally invasive aesthetic procedure in men. Despite various recommendations by experts on the use of onabotulinumtoxin type A in the literature, distinct guidelines for its use in males and females do not exist. OBJECTIVES: The aim of this study was to delineate safe and effective doses for the use of onabotulinumtoxin type A in males for...

Journal Article, Systematic Review

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tier1 To click or not to click - The importance of understanding the layers of the forehead when injecting neuromodulators - A clinical, prospective, interventional, split-face study. Journal of cosmetic dermatology · 2020 · PMID 33251687

Abstract summary (English) BACKGROUND: Differences in the effectiveness of neuromodulator treatments for horizontal forehead lines dependent on depth of product administration have been described. However, knowledge in respect to the fascial anatomy of the forehead still remains elusive. AIMS: To relate the fascial anatomy of the forehead to the effectiveness of neuromodulator treatments by conducting a clinical, prospective, interventional...

Journal Article, Randomized Controlled Trial

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tier1 Efficacy, Patient-Reported Outcomes, and Safety for Millennial Subjects Treated With OnabotulinumtoxinA for Moderate to Severe Horizontal Forehead Lines. Dermatologic surgery : official publication for American Society for Dermatologic Surgery [et al.] · 2020 · PMID 31625954

Abstract summary (English) BACKGROUND: Millennials (aged 18-34 years) represent a growing segment of the facial aesthetic market. OBJECTIVE: To evaluate investigator-assessed efficacy, patient-reported outcomes (PROs), and safety for millennials versus subjects aged at least 35 years after onabotulinumtoxinA treatment of forehead lines (FHL) across 2 phase 3 studies. METHODS: Eligible subjects with moderate to severe FHL received...

Clinical Trial, Phase III, Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't

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tier1 Efficacy, Patient-Reported Outcomes, and Safety in Male Subjects Treated With OnabotulinumtoxinA for Improvement of Moderate to Severe Horizontal Forehead Lines. Dermatologic surgery : official publication for American Society for Dermatologic Surgery [et al.] · 2020 · PMID 31343446

Abstract summary (English) BACKGROUND: Men represent a growing segment of the facial aesthetic market. OBJECTIVE: To evaluate investigator-assessed efficacy, patient-reported outcomes, and safety after onabotulinumtoxinA treatment of forehead lines (FHL) in men. METHODS: Subjects with moderate to severe FHL received onabotulinumtoxinA (frontalis: 20 U; glabellar complex: 20 U, with/without 24 U in crow's feet regions) or placebo in 6-month,...

Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't

View on PubMed

Suggested interpretation

Strong evidence base

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