Microtox: Small-Dose Botulinum Toxin Delivering Big Results 

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Botulinum toxin is undoubtedly the most well-known aesthetic injectable – and for good reason. It simply works… and not just for wrinkles! Dr Debbie Norval explores the many uses of botulinum toxin and unpacks some of the innovative approaches being taken today. 

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In the world of modern botulinum toxin treatments, a plethora of intriguing buzzwords has emerged. From “babytox” to “mesotox” and “microtox”, these fashionable terms pique our curiosity. In a world full of frozen, overprocessed faces, it’s no wonder that interest in gentler alternatives is growing. 

But what exactly are these techniques? Are they synonymous, or do they offer distinct approaches? Most importantly, do they work? Let’s delve into the dynamic world of these botulinum toxin innovations to uncover the answers.  

Babytox 

Babytox is when your aesthetic doctor injects smaller doses of standard dilutions of botulinum toxin in the traditional muscle areas (and at the typical depths). This is popular in younger patients, just starting out, who want to use neurotoxin as a preventive treatment method. It’s also popular with actors and actresses, as they prefer their neurotoxin to be subtle and to have worn off before their next big shoot.  

Babytox has its drawbacks. Because of the low doses used, babytox only lasts about six weeks. Small doses given every 6–8 weeks increase the risk of developing botulinum toxin resistance.  

Microtox 

Microtox is a highly diluted neurotoxin injected in much smaller doses, referred to as microdroplets. Rather than being injected into the muscle, microtox is injected much more superficially – intradermally – just underneath the skin. It’s injected using tiny 31- or 32-gauge needles. Microdroplets are injected in a linear fashion, about 1 cm apart, following a uniform grid pattern. 

Microtox is not only used to treat aesthetic concerns but a large group of medical conditions. Treatment is not permanent, and the condition will gradually return to its original state within 3–6 months.  

Mesotox and “microdroplet technique” are other terms used to describe microtox. 

In summary, babytox is a traditional or standard botulinum toxin treatment that just uses very low doses. It typically won’t last the full four months. On the other hand, microtox is diluted botulinum toxin injected very superficially into the skin in a grid pattern.

The multiple effects of botulinum toxin  

Did you know that botulinum toxin is not just for wrinkles? This fascinating and versatile drug is used to manage several medical conditions:  

1. Muscle relaxation: Botulinum toxin acts by inhibiting the release of a neurotransmitter called acetylcholine at the junction between nerves and muscles (the neuromuscular junction), resulting in temporary relaxing of the muscle involved.  

2. Reduction of glandular secretion: Botulinum toxin also inhibits the release of acetylcholine from nerve terminals that supply glands, thereby reducing glandular secretions.  

3. Anti-inflammatory effect: A lesser-known benefit of botulinum toxin is its anti-inflammatory effect. It inhibits the release of various inflammatory mediators, such as cytokines and chemokines, effectively reducing inflammation.  

4. Collagen induction: Recent studies have demonstrated that botulinum toxin increases overall collagen levels and decreases the degradation of collagen. Botulinum toxin upregulates the gene expression of collagen type I (mature collagen) but downregulates collagen type III (scar collagen). It decreases the production of some metalloproteinase enzymes, which are a group of enzymes that break down collagen.  

5. Pain control: By interfering with neurotransmitter release, botulinum toxin disrupts the communication between nerves and muscles, as well as between nerves involved in pain perception. This disruption reduces muscle hyperactivity, decreases nerve sensitisation, and dampens pain signalling in the affected area.  

Microtox uses in medicine 

Hyperhidrosis 

Hyperhidrosis is defined as excessive sweating, more than required to regulate body temperature. Patients suffering from hyperhidrosis are significantly affected at work and in social situations, leading to reduced physical and emotional well-being, difficulty in personal relationships, and social stigmatisation. Microtox is commonly used to treat excessive sweating of the palms, soles, or underarms. 

Our bodies produce sweat to cool down when we’re hot or nervous. The neurotransmitter acetylcholine normally signals our sweat glands to get to work, but microtox stops acetylcholine from doing its job. So, our sweat glands don’t get the message to produce sweat, which means we perspire less, and the sweat glands shrink.  

What’s interesting is that the effects last longer for sweating than for smoothing out wrinkles – sometimes up to six months. Scientists think there might be another way botulinum toxin helps reduce sweating, but it’s not yet fully understood. One theory is that it inhibits the sudomotor nerves that supply the muscles that cause sweat glands to contract. Since these muscles need to contract to release sweat, if they can’t contract, they can’t release as much sweat! 

Sebaceous glands and excess sebum production  

Sebaceous glands are responsible for producing sebum, the natural oil that lubricates our skin and hair. Microtox is used as a treatment for overactive sebaceous glands, which cause problems such as acne, sebaceous hyperplasia, an oily T-zone, and dilated pores.  

Like its action on sweat glands, botulinum toxin works by inhibiting the release of acetylcholine from the nerve endings that supply sebaceous glands. Botulinum toxin, therefore, prevents the nerve signals that would normally prompt the sebaceous glands to produce sebum. After microtox injections, the sebaceous glands temporarily become smaller and less active, with reduced sebum secretion. Reduction in the size of both sweat and sebaceous glands also has the wonderful effect of tightening the skin! 

Enlarged pores  

Sebaceous glands are part of the anatomy of a pore. Excess sebum production contributes to enlarged pores. Microtox reduces sebum production and the size of sebaceous glands, thereby shrinking pores over time. But that’s not all! 

Microtox increases collagen type I levels, which helps improve skin elasticity and firmness, potentially contributing to a reduction in pore size. 

In addition, muscles surrounding pores can contribute to their enlargement by exerting tension on the skin. By relaxing these muscles, microtox helps reduce the tension on the skin, leading to a visible improvement in the appearance of enlarged pores. 

Of course, the pores are still there. Pores are normal, and our skin must “breathe”, but they are smaller and have decreased sebaceous activity.  

Acne  

Microtox can help improve acne symptoms and prevent the formation of new breakouts. 

As we have learned, microtox helps reduce sebum production. Excess sebum production is influenced by hormones, which contribute to acne. Therefore, by decreasing sebum production, microtox indirectly helps control acne. 

Botulinum toxin has anti-inflammatory properties that help calm inflammation associated with acne lesions. By inhibiting the release of inflammatory mediators from nerves, botulinum toxin reduces the redness, swelling, and discomfort associated with acne breakouts. 

Rosacea and facial flushing  

Rosacea is a chronic inflammatory skin condition characterised by redness, flushing, visible blood vessels, and sometimes pimples or bumps. Rosacea is a complex condition with both neurogenic inflammation and neurovascular hypersensitivity.  

The anti-inflammatory effects of microtox block the release of inflammatory mediators from nerve endings, inhibiting inflammation and pathological angiogenesis (abnormal blood vessel formation). 

In rosacea management, botulinum toxin also inhibits the release of neurotransmitters other than acetylcholine from nerves. It blocks the release of perivascular neuropeptides, which are potent arterial vasodilators that cause facial flushing.  

Botulinum toxin also stimulates collagen production in the skin, leading to improvements in skin texture, quality, elasticity, and overall health. While not a direct treatment for rosacea, stronger skin means that superficial blood vessels are pushed back to where they belong: under the skin in the subcutaneous plane.  

Melasma 

Melasma is a common skin condition characterised by dark, pigmented patches typically appearing on the face, often triggered by hormonal changes, sun exposure, or genetics. 

Recent studies indicate that botulinum toxin can reduce pigmentation caused by UVB damage. UV damage triggers inflammation, and the primary mechanism of action for treating pigmentation with microtox is its anti-inflammatory activity, which affects various cytokines involved in pigment changes. Examples of inflammatory cytokines suppressed by botulinum toxin include prostaglandin E2 and interleukin-1 alpha. 

So, how does it work in this instance? Some theories suggest that botulinum toxin directly inhibits melanocytes, which are the cells that produce the pigment melanin and are derived from ectodermal tissue. Another theory is that the inhibition of acetylcholine suppresses melanocyte-stimulating hormone secretion, resulting in decreased melanin production. 

Although the microtox technique of intradermal injections is used for hyperpigmentation, the concentration of the botulinum toxin that gives the best results is the standard dilution (which means it is technically not microtox). 

Crêpey skin  

Microtox targets crêpey skin, addressing fine lines, wrinkles, and a thin, crinkled texture. Unlike traditional botulinum toxin injections, which target deeper facial muscles, microtox is injected superficially into the dermis, targeting tiny facial muscles responsible for fine movements. By temporarily relaxing these muscles, microtox smooths out the skin surface. 

Additionally, microtox stimulates fibroblast cells, promoting the production of collagen, elastin, and hyaluronic acid, enhancing skin hydration and texture. By increasing collagen levels, microtox helps strengthen the skin’s structure, thereby reducing the appearance of fine lines and wrinkles. 

Then, of course, microtox reduces pore size and sebaceous secretions, further refining skin texture. This – combined with hydration, increased collagen, and muscle relaxation – results in smoother, firmer, and more youthful-looking skin. 

Microtox particularly excels in the neck area, where the platysma muscle is attached to the neck skin. This is a thin, broad muscle that extends from the chest and shoulder area up to the lower face and jawline. Its fibres interlace with the fibres of the superficial layer of the neck skin. Microtox then has a dual action of smoothing out the muscle while improving the texture and strength of the crêpey neck skin. What a win! 

Scars  

Microtox offers promise in treating various scar types, including acne scars, surgical scars, keloids, and hypertrophic scars. 

By relaxing superficial muscles around scars, microtox injections decrease muscle tension, reducing scar contracture and promoting a softer, flatter appearance. 

Microtox’s anti-inflammatory properties aid in decreasing scar redness and inflammation by modulating inflammatory mediator release from nerve endings. 

By boosting healthy collagen levels, microtox enhances skin texture, elasticity, and structural support, diminishing scar visibility. Additionally, it can smooth out uneven or rough skin surfaces, such as those seen in acne scars. 

Microtox also helps alleviate pain and itching associated with scars. 

Keloids  

Keloid scars, marked by their raised, thickened appearance extending beyond the original wound, result from abnormal wound healing involving excessive collagen production. 

Fibroblast cells in these scars behave abnormally and produce an excess of scar collagen. Microtox targets keloids by modulating fibroblast cell activity, inhibiting their proliferation, regulating cell cycles, and preventing differentiation into myofibroblasts, in other words, promoting normal collagen synthesis. 

Chronic inflammation contributes to keloid formation. Microtox’s anti-inflammatory properties suppress inflammation, reducing scar size and symptoms like redness and itching. 

In areas of significant muscle movement, such as the chest and shoulders, muscle tension exacerbates keloid development. Microtox reduces muscle activity around keloids, easing tension and mechanical stress on scar tissue. 

Microtox also affects blood vessel formation and function. Keloids frequently exhibit increased vascularity, leading to their red or purple appearance. By inhibiting angiogenesis (the formation of new blood vessels) and reducing blood flow to keloid sites, microtox diminishes the vascular component of keloid scars. 

Itch 

Pruritus, or itch, is an uncomfortable sensation that often leads to scratching. When itching becomes chronic, it can cause significant distress and severely impact a person’s quality of life. 

Microtox shows promise in alleviating itching by targeting various mechanisms: it blocks neurotransmitter and neuropeptide release, inhibits mast cell degranulation, downregulates itch receptors, and suppresses inflammatory mediators like cytokines and interleukins, which are commonly associated with itching. 

Increased luminosity  

Microtox causes relaxation of the muscles that would normally activate lymphatic channels. This can lead to mild dermal fluid retention, resulting in a temporary luminous appearance lasting around three months. The increased luminosity – along with smoother, more relaxed skin, reduced pore size, diminished sebaceous secretions, and decreased redness – contributes to a hydrated, radiant, and youthful appearance. 

It’s important to note that while the luminosity might look lovely, too much fluid retention could lead to undesired effects like under-eye puffiness and malar festoons (a puffy upper cheek area). It might be better and cheaper to use a bit of Vaseline instead!  

Conclusion 

As research continues to unveil the full extent of botulinum toxin’s potential, we’re witnessing groundbreaking advancements in addressing diverse dermatological and cosmetic concerns. From minimising sweat and sebum production to improving skin texture and reducing inflammation, botulinum toxin treatments offer transformative outcomes and a renewed sense of confidence.

With each innovation, we’re not just enhancing appearances – we’re empowering individuals to embrace their best selves, inside and out.  

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References  

1. Jung, J.A., Kim, B.J., Kim, M.S., You, H.J., Yoon, E.S., Dhong, E.S., Park, S.H., & Kim, D.W. (2019). Protective Effect of Botulinum Toxin against Ultraviolet-Induced Skin Pigmentation. Plastic and Reconstructive Surgery, 144(2), 347-356.  

2. Wu, W.T.L. (2015). Microbotox of the Lower Face and Neck: Evolution of a Personal Technique and Its Clinical Effects. Plastic and Reconstructive Surgery, 136(5 Suppl), 92S-100S.  

3. Lim, S.H., Sun, Y., Goh, C.L., & Kim, J. (2021). Intradermal microbotox: a review of current evidence on its use for aesthetic indications. Journal of Cosmetic Dermatology, 20(6), 1516-1524. 

4. Lee, H.K., Kim, M.C., Yoon, H.C., Lee, W.J., & Cho, S.B. (2019). The efficacy of intradermal injection of botulinum toxin type A for the treatment of hypertrophic scars and keloids: a systematic review and meta-analysis. Aesthetic Plastic Surgery, 43(6), 1550-1558. 

5. Gazerani, P. (2022). How Does Botulinum Toxin Inhibit Itch? Toxins (Basel), 14(10), 701.  

6. Oh, S.H., Lee, Y., Seo, Y.J., Lee, J.H., Yang, J.D., Chung, H.Y., & Cho, B.C. (2012). The potential effect of botulinum toxin type A on human dermal fibroblasts: an in vitro study. Dermatologic Surgery, 38(10), 1689-1694.  

7. González, C., Franco, M., Londoño, A., & Valenzuela, F. (2020). Breaking paradigms in the treatment of psoriasis: Use of botulinum toxin for the treatment of plaque psoriasis. Dermatologic Therapy, 33(6), e14319.