As an aspiring dermatologist, I was often curious about the differences between all of the different types of botulism toxins. As it turns out, according to Dr. Cheryl Burgess’ Cosmetic Dermatology, there are four brands and two types currently utilized by physicians: Botox Medical (Allergan), Botox Cosmetic (Allergan), Dysport (Speywood Pharmaceuticals), and Myobloc (Elan Pharmaceuticals). The differences, which are reported from Cosmetic Dermatology, are outlined below.

Botox Medical

Botox Medical is the form of botulism toxin which has been used for the longest amount of time, having been approved by the FDA in 1989. Like Botox Cosmetic and Dysport, it is botulism toxin type A, which is the most potent of all eight serologically distinct botulism toxins. It is currently approved in over 70 countries, and is used for non-cosmetic conditions such as starbismus, blepharospasm, hyperhidrosis, poststroke spasticity, back spasm, and headache.

Botox Cosmetic

Botox Cosmetic was approved by the U.S. FDA in April 2002 for treatment of moderate to severe glabellar lines in patients 65 years of age or younger. Like Botox Medical and Dysport, it is potent botulism toxin type A. It is commonly used between the eyebrows, on crow’s feet, horizontal forehead lines, neck lines, melolabial folds, and other hyperkinetic facial lines.

Dysport

Dysport is a third form of botulism toxin type A, but unlike Botox Medical and Botox Cosmetic, is not manufactured by Allergan. Like Botox Medical, Dysport is not currently used for cosmetic purposes anywhere in the world. (Besides, this study found Botox Cosmetic was more effective in treating glabellar lines, anyway.) Dysport has been used in the United Kingdom for medical purposes since the early 1990’s and has been used for blepharospasm, hemifacial spasm, and spasmodic torticollis.

Myobloc

Myobloc is distinct from the other three botulism toxins in that it is type B. This is promising, as continued use of one type of botulism toxin leads to the body’s eventual production of neutralizing and nonneutralizing antibodies; however, antibodies to one serotype (say from continued exposure to type A Botox Cosmetic) do not cross-neutralize another serotype (say type B Myobloc). Of course, according to Dr. Cheryl Burgess’ Cosmetic Dermatology, this type of resistance has occurred only in 3-5% of patients. Still, patients in the U.S. can consent to off-label use of Myobloc for cosmetic purposes because Myobloc is FDA approved for the treatment of cervical dystonia, and the safety and efficacy of Myobloc for cosmetic purposes has been demonstrated in several small studies.