INTRODUCTION
Dermatologically, based on the level of sebum excretions we can classify the facial skin type in dry, neutral, oily, or mixed.1 Oily skin is a blemish that affects a high percentage of the population with a prevalence of women. It's characterized by enlarged, clearly visible pores a glossy shine thicker, pale skin.2 Oily skin is prone to comedones (blackheads and whiteheads) and to the varying forms of acne. Together with other skin imperfections, oily skin represents a limitation in social relationships for many people.3 In the last year due to the obligation of wearing masks to avoid COVID-19 infection, a large increase in the number of patients with acne and oily skin has been observed.4-6 Wearing a face mask for long periods of time increases the temperature and humidity on the surface of facial skin caused by exhaled air and perspiration.7,8
Several therapies are proposed for the treatment of oily skin with very variable success rates. Among these therapies, the most common ones are represented by topical ones based on various cosmetics and retinoids; systemic therapies are represented by the chronic use of contraceptives, spironolactone, and isotretinoin. Oral therapies, which must be used for long periods, are not free from serious side effects such as changes in menstrual periods, breast tenderness, venous thromboembolism when using oral contraceptives, and teratogenicity with the use of isotretinoin.9 Several authors have recently evaluated the use of onabotulinumtoxin-A (BoNT-A) in the treatment of this pathology.10 At present it has not yet been fully demonstrated how it can be the active toxin on the sebaceous gland. Among the various hypotheses proposed by the various authors, certainly, the most accredited hypothesis is linked to the ability of botulinum toxin to act on the nicotinic acetylcholine receptor α7 capable of releasing acetylcholine as a local cytotransmitter in an autocrine and paracrine way.11-13
Various authors who have demonstrated the validity of the use of BoNT-A have confirmed that to yield valid results it is necessary to inject the toxin in small units very superficially into the dermis and homogenously over the entire treated area.14-17
The injections must be performed with a distance of no more than 1 square cm and intradermally. Therefore, the procedure is often painful for patients and often accompanied by complications such as bleeding, bruising, and hematoma.
Several therapies are proposed for the treatment of oily skin with very variable success rates. Among these therapies, the most common ones are represented by topical ones based on various cosmetics and retinoids; systemic therapies are represented by the chronic use of contraceptives, spironolactone, and isotretinoin. Oral therapies, which must be used for long periods, are not free from serious side effects such as changes in menstrual periods, breast tenderness, venous thromboembolism when using oral contraceptives, and teratogenicity with the use of isotretinoin.9 Several authors have recently evaluated the use of onabotulinumtoxin-A (BoNT-A) in the treatment of this pathology.10 At present it has not yet been fully demonstrated how it can be the active toxin on the sebaceous gland. Among the various hypotheses proposed by the various authors, certainly, the most accredited hypothesis is linked to the ability of botulinum toxin to act on the nicotinic acetylcholine receptor α7 capable of releasing acetylcholine as a local cytotransmitter in an autocrine and paracrine way.11-13
Various authors who have demonstrated the validity of the use of BoNT-A have confirmed that to yield valid results it is necessary to inject the toxin in small units very superficially into the dermis and homogenously over the entire treated area.14-17
The injections must be performed with a distance of no more than 1 square cm and intradermally. Therefore, the procedure is often painful for patients and often accompanied by complications such as bleeding, bruising, and hematoma.
