For some women, periodic injections of BOTOX Cosmetic® have become almost as routine as semi-annual teeth cleaning or regular mammograms. Indeed, Botox treatment has become the leading cosmetic procedure in the U.S., with more than 2.5 million treatments in 2009, says the American Society for Aesthetic Plastic Surgery.
But how well do we understand the possible long-term effects of frequent Botox usage? Perhaps not well enough, suggests a University of Calgary study.
Five members of the Faculty of Kinesiology at the University set out to study the long-term effects of Botulinum Toxin A, the ingredient in Botox that paralyzes muscles to smooth facial wrinkles. Their research followed up an earlier study by one of the faculty, Dr. Walter Herzog, that proved the neurotoxin can cross muscle membrane barriers and affect nearby tissues that haven’t been injected directly.
As reviewed by the science blog site, Science 2.0, the current study performed on animals shows that, “over time, Botulinum toxin A use also results in muscle weakness, atrophy and loss of contractile tissue in non-injected muscles far-removed from the injection site.” In fact, according to Science 2.0, the researchers themselves were surprised at the degree of muscle loss in areas far removed from the injection sites.
This study was performed using doses of Botulinum Toxin A suitable for combating cerebral palsy—doses much larger than those used to treat facial wrinkles. And the researchers acknowledge that for these kinds of uses, the possible long-term consequences suggested by the study might be a worthwhile tradeoff. Nevertheless, Dr. Herzog believes that the results of the study “should be valid for any application of the drug.”
If you take advantage of Botox to banish wrinkles, should you immediately discontinue treatment? It’s hard to say. One of the Canadian researchers, Dr. Rafael Fortuna, is quoted on Science 2.0 saying, "I think it's fair to say that the paper raises some important questions about the long-term therapeutic use of Botox, especially with children and adolescents.