Botulinum Toxin Type A (Botox Cosmetic)
One of the cosmetic reasons people use botulinum toxin type A (Botox®) is to temporarily improve the appearance of wrinkles between the eyebrows (commonly called frown lines). In 2009, the generic name for Botox was changed from "botulinum toxin type A" to "onabotulinumtoxinA." This was done to prevent confusion between Botox and Dysport® (abobotulinumtoxinA), a new botulinum toxin type A product.
When used cosmetically for frown lines, this drug works by entering nerve cells and inhibiting the release of acetylcholine, a chemical that transmits signals from nerve to nerve. The actions of the medication are not permanent, however, and the muscle will eventually recover and return to its previous state.
(Click OnabotulinumtoxinA for more information on this product, including possible side effects, cases in which the drug may need to be avoided, and whether women who are pregnant or breastfeeding can use it.)