An active ingredient called botulinum toxin type A, is derived from Clostridium botulinum, a type of bacteria. The toxins role is to stop nerves from carrying out their normal function. By preventing the release of significant chemicals, muscle contraction is also inhibited. The positive effect is to make muscles between the eyebrows relaxed, diminishing the appearance of vertical frown lines. The effect is only temporary and further treatments can be given every three months.