When BOTOX® is injected into a muscle it activates a process called selective muscle denervation.
This is when the neuromuscular junction – where the nerve and muscle meet – has its receptors blocked from acetylcholine: the chemical which forces the muscle to contract.
Therefore, even though the nerve continues to send a signal which requests movement, the tissue does not receive the instruction and the muscle remains still.
Over 3-5 months, the muscle gradually grows new receptors and is able to contract again.
Botox is most effective in the correction of lines which are formed from muscle contractions alone. Because the underlying muscle doesn’t move, the skin above it no longer creases.
Thus, the effects of BOTOX® are most noticeable in frown and laughter lines.
BOTOX® does not remove wrinkles which are permanently engraved in the skin, regardless of muscle movement, although it may soften them.