Dr. Cara McDonald

And these are the nerves that tell our muscles to contract.

So

the toxin gets taken up into the nerve terminal and then the normal neurotransmitter, which is the chemical that tells our muscle to contract, it normally comes out of the end of the nerve and goes to the muscle receptor.

It can't get out of the end of the nerve anymore because that little receptor that it attaches to is gone.

And so essentially, it reduces the muscle contraction of that muscle locally.

And that lasts about three to four months until little new receptors regrow to replace the ones that were destroyed by the injection.

And so when your brain or your body tells the muscle to contract, the nerve just doesn't release the signal.

So the muscle doesn't contract anymore.

And of course, what that does is it stops the muscles from contracting that create the lines, some of the lines on our face.

So we call them dynamic wrinkles, which are the ones that are due to muscle contraction.

But of course, we can't treat all dynamic wrinkles because, for example, some lines like around my mouth,

are a dynamic wrinkle, but we don't want to freeze a muscle that helps us smile.

So we can only treat the ones that are generally negative expressions that we're happy to live without.

But as I said before, what a lot of people don't appreciate is that we also can target muscles in the face that...

contribute to the aging process.

So they're called the depressor muscles in the face.

So the typical ones are the corners of the mouth that bring our mouth down, the brow when we frown, you can see it comes down, the neck pulls our mouth and whole face down.

Mm-hmm.

And so these depressor muscles, they don't actually cause wrinkles, but they contribute to the way we age and they accelerate aging.

Everyone thinks gravity is our problem, but the muscles in the face are very strong and those depressor muscles contribute to the sag over time.