Trends in Botulinum Toxin: Bro-tox, Scro-tox, and Scalp-tox

Botulinum toxins have been one of the most successful medications in the cosmetics industry. Botulinum toxins are now a multi-billion dollar industry and are effective in reducing wrinkles and giving people a more youthful appearance. Among the several types of botulinum toxins, the most commonly used for cosmetics is botulinum toxin type A. Currently there are three brands of botulinum toxin, type A: 

Botox® – onabotulinumtoxinA

Dysport® - abobotulinumtoxinA

Xeomin® - incobotulinumtoxinA

FDA approval is limited to the lines in between the eyebrows (known as the glabellar lines or the “elevens”) and the smile lines on the sides of the eyes (known as lateral canthi lines or “crow’s feet”). However, many licensed practitioners are able to use the botulinum toxin off-label for injections elsewhere.

Here are three trending botulinum toxin uses:

Bro-tox

Botulinum toxin injections are predominantly done in women but men also want to be a part of the action. Any wrinkle that forms in women will form in men, too, including the “elevens” and “crow’s feet.” With the rise in demand among men for botulinum toxin injections, more and more practitioners are getting comfortable with injecting men. One nuance in men is that males have stronger facial muscles and typically need higher doses to get the same effect.^[1] This also means that for a given dose of botulinum toxin, the effect may not last as long in men as it does in women. In one study that evaluated the effects of injecting the standard recommended dose of 20 units into the glabellar muscles (the location of the “elevens”), 80% of men lost the effects by 2 months and 85% lost the effect by 3 months.^[1]

Pros: Botulinum toxin injections work well in men to reduce the appearance of wrinkles.

Cons: Higher doses may be needed to achieve lasting results, which can lead to a bit more of a hit to the pocketbook.

Scro-tox

Scrotox refers to the injection of botulinum toxin into the scrotum. As painful as this sounds, men are flocking to have this done for cosmetic reasons. The scrotum contains the dartos and the cremaster muscles that work together to move the testicles and help regulate the temperature of the testicles. The cremaster muscles contract to pull the testicles closer to the body when it is too cold and relax when it gets too hot. The dartos muscle lies just underneath the skin and contraction of this muscle results in the wrinkly appearance of the scrotum. The dartos muscle contracts to decrease the surface area of the scrotum to reduce heat loss and relaxes to increase the surface area of the scrotum, thereby promoting heat loss.

The injections are done superficially just past the skin and not into the testicles. When botulinum toxin is injected into these muscles, the scrotum may look more smooth and hang lower, giving the illusion of a larger, more enhanced male package. However, the effects on male fertility as a result of possible impaired temperature control is unknown. 

Botulinum toxin injections into the scrotum have also been performed for groin sweating and chronic scrotal pain caused by painful contractions of the scrotum.^[2] There are two kinds of sweat glands found in the scrotal area: eccrine and apocrine. Botulinum toxin reduces the function of the eccrine sweat glands but the apocrine sweat glands may remain active. The end result is that embarrassing groin sweat may lessen but the glands responsible for body odor and pheromones may continue to be active. 

Pros: Botulinum toxin injection in the scrotum may lead to a smoother, lower hanging sac and may reduce groin sweating.

Cons: Relaxation of the dartos and cremaster muscles may impair temperature control in colder environments, which may or may not affect sperm viability.

Scalp-tox

A common medical (non-cosmetic) purpose for botulinum toxin is to treat hyperhidrosis, a condition characterized by excessive sweating. The injections are most often performed for the armpits, palms, and soles. An emerging trend is an injection into the scalp. This has been shown to reduce not only sweating, but also alleviate headaches. It has been FDA-approved for prophylactic treatment of chronic migraines since 2010.^[3] When done for sweating, you can work out without developing a sweaty scalp. When the scalp is less sweaty, the idea is that your hair will stay fresh and dry.

Sweat serves an important function in temperature regulation, especially in times of exercise or overheating. Heat loss from the scalp is important for selective brain cooling^[4] during times of increased body temperature (such as hot weather or exercise). The use of headgear has been shown to hinder the scalp’s ability to cool the head.^[5] When scalp sweating is reduced with botulinum toxin injections, care must be taken so that the scalp does not overheat during times of exertion or hot weather. 

Pros: Botulinum toxin injections to the scalp may help reduce sweaty hair and headaches.

Cons: Scalp sweating may be important in cooling the head, and this function may be impaired after botulinum toxin injections.