One of the most common misconceptions about Botox injections is the concept of “Weak Botox”. Patients will ask me if I use the strong kind, or the will complain that a previous physician used diluted Botox and that it didn’t last very long. But as long as you always think about your Botox in terms of units, then you don’t have to worry about its strength.
When I pull a new vial of Botox out of the freezer (it has to be stored cold), I have to reconstitute it. It comes as a dry powder in an otherwise empty bottle. I have to add saline solution to the bottle, in order to be able to inject it in the liquid form. This reconstitution process is where the idea of dilute Botox comes from. Because an physician has to add saline to the bottle, it seems like the physician can then determine how dilute (weak) or concentrated (strong) the Botox will be.
But every bottle of Botox has the same number of units in it – 100. So as long as your Botox is injected in and priced by units, it really doesn’t matter how much liquid the provider reconstitutes it with. If a small amount of saline is used to reconstitute, then only a small amount of volume will be needed per unit. If a large amount of saline is used to reconstitute, then a larger volume of solution will be injected per unit. I personally reconstitute my Botox with a very low amount of saline. This means that my concentration is strong but since I inject by unit rather than by volume, it really doesn’t matter in terms of effect. It does matter however in terms of patient comfort. Lower injection volumes are more comfortable.
Its the number of units injected by the physician that determines the degree of muscle relaxant effect and the length of that effect. The more units that I inject into the brow, the more relaxation will be achieved and the longer it will last.
Where the unit concept is most important for the consumer is when it comes to pricing Botox. Always choose a provider who prices their Botox by the unit. Then you will know exactly how much you are getting. If you buy your Botox injections based on a per area price (i.e. $200 for the brow and $150 for the forehead), this allows the provider the opportunity to use fewer units than actually needed, and you very well may find that your Botox doesn’t last nearly as long as it should.