Therapeutic Use of Botulinum Neurotoxins in Dermatology: Systematic Review

Abstract

Botulinum toxin is a superfamily of neurotoxins produced by the bacterium Clostridium Botulinum with well-established efficacy and safety profile in focal idiopathic hyperhidrosis. Recently, botulinum toxins have also been used in many other skin diseases, in off label regimen. The objective of this manuscript is to review and analyze the main therapeutic applications of botulinum toxins in skin diseases. A systematic review of the published data was conducted, following Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Botulinum toxins present several label and off-label indications of interest for dermatologists. The best-reported evidence concerns focal idiopathic hyperhidrosis, Raynaud phenomenon, suppurative hidradenitis, Hailey–Hailey disease, epidermolysis bullosa simplex Weber–Cockayne type, Darier’s disease, pachyonychia congenita, aquagenic keratoderma, alopecia, psoriasis, notalgia paresthetica, facial erythema and flushing, and oily skin. Further clinical trials are still needed to better understand the real efficacy and safety of these applications and to standardize injection and doses protocols for off label applications.

Toxicology and pharmacology of botulinum and tetanus neurotoxins: an update

“…The strong efficacy and safety profile of BoNT-A1 for hyperhidrotic conditions has driven clinicians to evaluate its therapeutic potentiality in many other cutaneous diseases (Guida et al 2018 ). Scar prevention, as well as vascular and inflammatory skin disorders, oily skin, alopecia, rhytides and cutaneous lesions, are some of the novel indications for BoNT in cosmetic and notably non-cosmetic aspects of dermatology (Martina et al 2021 ; Naik 2021 ). These emerging clinical applications stem also from recent evidence that the BoNT/A1 receptors and intracellular targets are not unique for neurotransmission.…”

“…More recent retrospective reviews have suggested the role of the intradermal injection of BoNT-A1 in decreasing sebum production and pore size with high patient satisfaction without significant side effects (Shuo et al 2019 ). Intradermal BoNT-A1 injection may represent an innovative promising treatment for oily skin and other relevant dermatological problems, such as enlarged pores, acne, and seborrheic dermatitis (Martina et al 2021 ).…”

“…In a preclinical study in a mouse model of psoriasiform dermatitis, intradermal injections of BoNT-A1 lead to significant improvement over placebo and a reduction in skin lymphocyte infiltration (Ward et al 2012 ). Moreover, the high concentration of nerve fibres in psoriatic skin present together with an increased level of CGRP and SP of sensory nerve origin lead to the hypothesis that the toxin inhibits CGRP- and SP-derived nerve release with clinical remission of the disease (Martina et al 2021 ; Amalia et al 2021 ).…”

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

“…Additionally, the authors conducted an in vitro study, suggesting inhibiting TGF-B1 secretion from the hair follicles by the intradermal injection of botulinum toxin may be the potential action mechanism of BoNT-A in treating AGA. Despite the promising results of the mentioned research, recently published systemic reviews underline that there is still a need to conduct randomized, placebo-controlled studies in this area [ 55 , 56 , 57 ].…”

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

“… 52 Due to its unique versatility, BTX is also being used in many other dermatologic conditions, in off label regimen. 53 In a recent pilot animal study, is has been used experimentally to investigate its effect on hair follicle cell regeneration under continuous stress conditions. The authors concluded that BTX may be a positive indicator for hair loss treatment but future studies are warranted.…”