Botulinum toxin is a neuromodulator that works by preventing your nervous system from telling certain muscles to flex. It is derived from the same bacteria that causes botulism. However, it does not put patients at risk for botulism since the neurotoxin is diluted to less than 100 times the amount it would take to cause botulism. Furthermore, it is injected directly into targeted muscles with very little spread, so there is no systemic involvement.
Botulinum toxin injections target specific muscles that cause lines and wrinkles near the injection site. It does not “freeze” your whole face or alter your facial expressions when administered by a trained professional. Any undesired effects from this treatment usually come down to too much being given, or placement in the wrong muscles.