Botox® is used to weaken muscles that cause active lines of the face and is most successful in the center of the forehead.
Botox® is a neurotoxin. A neurotoxin is a chemical which is poisonous or damages nerve cells. Botox® comes form a bacteria called Clostridium botulinum. This bacteria produces at least eight distinct toxins but type A (BTX-A) is the one most commonly used in medicine.
It has its effect by preventing the release and uptake of a chemical called acetylcholine at the junction between the nerve and the muscle. Since the chemical is needed for the muscle fibres to receive the nerve impulse the muscle is essentially cut off from the nerve and therefore paralyzed.
With time the muscle may thin and weaken. This is called atrophy. In most cases however the connections between the nerve and the muscle re-grow and function is restored.
In the laboratory the toxin is purified from the bacterial culture by a complex series of steps that involves re-dissolving the toxin protein in a solution that contains albumin. This is then vacuum dried. It is distributed to the doctor in a freezing container and must remains frozen until just before use.