Botox exerts its effects through a muscle weakening or paralyzing effect. Like all drugs, its effectiveness is going to be dose-dependent. How much Botox® is injected will determine how much weakening of the muscle will occur and to what degree of improvement is seen in the undesired facial expression. The higher the dose given, the better the result. (up to a certain point)
To the best of current medical knowledge, it does not appear that humans vary much, if at all, in their responsiveness to Botox®. Contrary to some popular belief, patient susceptibility (how well does it work) is not different. To say that some patients are better responders or get better results with Botox® injections is probably not true. There may be other reasons why some patients have different results (e.g., such as how it is mixed, how old the solution is) but it is not because their muscles are more receptive or more resistant to the uptake of the Botox® molecules. Botox® effectiveness is as simple as the dose….per the amount of muscle into which it is injected.
This is why men usually require much higher doses of Botox® to get the same effect as women. They simply have more muscle mass in their face than women, usually because they are bigger in size and may have more weight. The more muscle thickness and surface area size to it, the more Botox® solution will be needed. However, most men can tolerate less of a profound effect as they usually are not interested in dramatic facial changes. When it comes to men, I usually up my Botox® doses about 20% for the same size area that I would inject in women. I also feel that Botox® doesn’t last quite as long in men than women, but there is not much scientific information to back that up. It just seems logical to me that more active surrounding muscle can overcome the effects of Botox® quicker.
By far and away, the most common area to inject Botox® for men is into the glabellar or eyebrow furrowing area. This can make a dramatic difference in that squinting or frowning appearance. Men seem to tolerate more horizontal forehead creases than women and that is good…as it takes lot of drug ( and cost) to get a profound forehead change in men. Some men may also want the crow’s feet area, to the side of the eye, treated as well but this is less common.
Dr. Barry Eppley
Indianapolis, Indian