How Does Botox Work? A Surprising Wrinkle

Okay, there’s no surprising wrinkle (aside from the fact that a toxin that can kill humans is used to treat wrinkles). I just felt like putting that in the title. But how exactly does Botox work? Let’s go.

 

A Little Science

When people say Botox, they’re using the short form of botulinum toxin, a toxin that derives from a bacterium called Clostridium botulinum.

The toxin acts at nerve endings and prevents the transmission of a signal from the nerve to the muscle that the nerve controls, thus causing paralysis of the muscle. (If you want to get more technical, the toxin prevents the release of a neurotransmitter called acetylcholine at the neuromuscular junction, thus preventing muscle contraction.)

The disease associated with this phenomenon is called botulism, generally acquired via infected wounds or the ingestion of contaminated foods (often homemade). If the toxin affects muscles that control breathing, the disease can be deadly.

While seven types of botulinum toxin (A, B, C1, D, E, F, and G) produced by different strains of the bacterium have been identified, when it comes to using the stuff on purpose (see below), only the first two are relevant.

 

The Medicine(s)

The idea of strategically using botulinum toxin in limited doses at desired locations to “turn off” muscles that are performing undesired actions began to gain traction in the 1970s, specifically for manipulating eye muscles contributing to strabismus (crossed eyes). By the early 1990s, reports of use for cosmetic purposes surfaced, and the little toxin that became known as Botox began its trajectory toward the big time.

It turns out that while Botox is used in day-to-day conversation (and in this article) to refer to any form of botulinum toxin, it technically refers to one specific brand of botulinum toxin type A. Other botulinum toxin type A formulations available in North America go by brand names that include Dysport, Xeomin, and Jeuveau.

Some nuances may exist in regards to the pros and cons of these various concoctions—all with the same active ingredient but delivered in combination with different substances—though I’ll leave that discussion to your favorite Botox professional.

The one formulation of the less-studied botulinum toxin type B available in North America typically goes by the trade name Myobloc.

 

Uses

As mentioned above, Botox is a part of the modern metropolitan experience due to its utility in cosmetic affairs, namely that of paralyzing facial muscles that contribute to things like frown lines, forehead lines, and crow’s feet (fine lines and wrinkles around the eyes).

That said, the treatment can be of use in a wide (and constantly expanding) range of conditions that result from involuntary muscle contractions. Examples include cervical dystonia (extreme contraction of the neck muscles), blepharospasm (tight closure of the eyelids), myoclonus (muscle jerks), and overactive bladder.

The dose of the toxin used varies depending on the exact condition that is being treated.

Interestingly, Botox is also being used to treat entities that, at least on the surface, are not directly attributable to undesired muscle contractions. Falling into this category are things like migraine headaches, hyperhidrosis (excessive sweating), and even depression.

 

Issues

If botulinum toxin is injected into the wrong muscle group or spreads from the desired site to nearby muscles, paralysis of these muscles can occur. In a cosmetic setting, this usually just results in the temporary appearance of goofy facial expressions, though difficulty swallowing and ptosis (drooping of the eyelid) are possible if the relevant muscles are involved.

Injection related bruising can obviously occur, and, as with most medicines, flu-like symptoms, headaches, and allergic reactions have been reported.

Of course, even if everything goes perfectly, the desired action of the toxin tends to dissipate over three to six months, necessitating reinjection if so desired.

The need for higher doses over time has been reported. Alternatively, because muscles that are affected go through a period of inactivity, they may slowly atrophy and therefore require progressively lower doses to stop acting up.

 

So how does Botox work? Go ahead and smile now that you have a general idea. Actually, skip the smile—you’ll end up needing Botox.