Home Ask The Doctor Can anti-wrinkle injections cause the brain to stop using a muscle, resulting in a permanent effect?

Can anti-wrinkle injections cause the brain to stop using a muscle, resulting in a permanent effect?

I’ve had countless doctors say that anti-wrinkle injections to the masseter will eventually become permanent, because the brain stops signalling one to use the treated muscle. If masseter muscles can be permanently affected by the injections, isn’t it likely upper cheek muscles around the eye can also be permanently affected? Why would the brain reprogram muscle use in the jaw and not in other parts of the face?

Anti-wrinkle injections work at the junction of the nerve and the muscle, an area known as the synapse, and block the transmission of nerve impulses to the muscle. The muscle then fires less, meaning less wrinkles due to skin creasing. Anti-wrinkle injections have a limited period of action, generally twelve weeks on average. Of course, everybody is different and in some people the effect will be longer or shorter. The length of action also depends on the dose (number of units used), the size of the muscles treated, and injection method. The action is not permanent.