The active ingredient in Botox is the botulinum toxin, although it is significantly diluted before being used to soften wrinkles.
Used as a medical treatment prior to its FDA approval for cosmetic use, Botox works by relaxing muscles through a mild weakening effect. Many of the wrinkles in the face stem from muscular contractions from an expression, such as:
Careful injection of botulinum toxin causes the contracting muscle to relax, and with that action, the skin naturally smooths over the relaxed tissue. There are no effects on lines and wrinkles that result from loss of skin elasticity and collagen alone, or lines present at rest without muscle movement. For this reason, Botox treatments work best in combination with other cosmetic treatments.
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