A Botox unit is the amount of botulinum toxin (the active ingredient in Botox that gives it its wrinkle-reducing powers). Botox units are a way for your injector to measure precisely how much Botox they administer. The more units injected, the more muscle-relaxing capabilities Botox has.
Botox units are also how injectors price the treatment. Botox cost can equate to a per unit dollar amount or a range of units, ranging from $10 per unit up to $20 per unit. For example, to determine the Botox cost of treating crow’s feet, which typically requires 10 to 20 units per side, the per unit price is multiplied by the number of units used, which varies from person to person.