What exactly is Botox, and how does it work?

By: Dr. Sean Delaney


Botox is a brand name for a type of Botulinum toxin (onobotulinum toxin A); much like the brand names Q-tip, Band-aid, and Kleenex have come to represent cotton tip applicators, adhesive bandages, and tissue paper. However, Botox isn’t the only game in town, as other similar types of Botulinum toxins available on the market include:

  • Dysport (abobotulinum toxin A).
  • Myobloc (rimbabotulinum toxin B).
  • Xeomin (incobotulinum toxin A).
  • Jeuveau (prabotulinum toxin A).
  • Daxxify (daxibotulinum toxin A).

Botulinum toxin is a naturally occurring toxin formed by the bacterium Clostridium botulinum. Most of the time, this bacterium exists in small enough quantities that make them harmless. However, in certain instances, such as improperly prepared canned foods, this bacteria can multiply and generate dangerous levels of toxins that, when ingested, can lead to a rare but severe illness known as Botulism.

The botulinum toxin works by preventing the release of the neurotransmitter acetylcholine from nerve endings. Acetylcholine is an essential messenger molecule for neurons that control muscles and sweat gland activity. When the target tissue of the toxin is a muscle, weakness or paralysis occurs. When the target is a secretary gland or oil gland, secretion is reduced or blocked.

Physicians have learned to take advantage of the action of botulinum toxin and use it to their advantage. Using small, safe doses of botulinum toxin, we can paralyze facial muscles to relax wrinkles. Because sweat production is also regulated by acetylcholine, Botox can be used to treat those with sweaty palms or armpits. Botox can also improve skin appearance by decreasing oil production and skin pore size.

Botox takes 24 to 72 hours to begin to have an effect, reflecting the time necessary for the toxin to diffuse and block the neuron junctions. The full effect of Botox peaks at around day ten, and the results typically last 3 to 4 months.

The good and bad thing about Botox is its effects eventually wear off. Over several months, the body’s neurons respond to and eventually bypass the blockade created by the botulinum toxin. This is good in that no treatment is ever permanent, so if you do not like the results of an injection, it is only temporary. This is bad because you need about three injections yearly to maintain your Botox results. However, we have found that with repeated Botox injections, some patients only need injections every six months.

It is important to note that patients can sometimes form neutralizing antibodies that render their Botox less effective. This may occur after injection of high doses of Botox (>200 units) per session or multiple injections within a 1 to 2-month Period. Unfortunately, limited information is available on whether the antibodies resolve over time, but we have found switching between the different types of known botulinum toxins usually solves this issue.

Factors that may cause Botox to wear off sooner than expected include:

  • High metabolism
  • Increase muscle usage (those who are naturally more expressive)
  • Which area is being treated (forehead and crows feet will last longer than areas treated around the mouth where there is more activity)
  • The amount of Botox injected (larger muscles require more Botox)
  • Inconsistent Botox injections (those with regular injections will last longer than those who have injections once or twice a year)
  • Development of neutralizing antibodies to Botox
  • Suboptimal injection technique

When receiving facial injections, it is vital that you only trust your face to someone who knows the facial anatomy well. At FPSA, our facial injections are performed by Dr. Delaney and Dr. Kridel, both board-certified facial plastic surgeons.

* All information subject to change. Images may contain models. Individual results are not guaranteed and may vary.