| The cosmetic form of botulinum toxin, often referred | | | | drug for the treatment of strabismus, hemifacial |
| to by its product name Botox, is a popular | | | | spasms, and blepharospasm. BOTOX is distributed in |
| non-surgical injection that temporarily reduces or | | | | 100-unit vials.The original batch of neurotoxin |
| eliminates frown lines, forehead creases, crows feet | | | | prepared by Shantz in November 1979 (designated |
| near the eyes and thick bands in the neck. The toxin | | | | batch 79-11) constituted the original BOTOX |
| blocks the nerve impulses, temporarily paralyzing the | | | | formulation and was used until December 1997. It |
| muscles that cause wrinkles while giving the skin a | | | | was replaced by a new neurotoxin complex batch |
| smoother, more refreshed appearance. Studies have | | | | designated BCB 2024. The new bulk batch is 5-6 |
| also suggested that Botox is effective in relieving | | | | times more potent on a weight basis. In a 100-unit |
| migraine headaches, excessive sweating and muscle | | | | vial, only 4.8 ng of neurotoxin is needed compared to |
| spasms in the neck and eyes. Botulinum neurotoxin is | | | | 25 ng of 79-11. The new BOTOX is comparable in |
| produced by the gram-negative anaerobic bacterium | | | | clinical efficacy and safety to the old, and a unit dose |
| Clostridium botulinum. | | | | of new BOTOX provides an equivalent response to |
| Eight serologically distinct botulinum neurotoxins exist, | | | | the same unit dose of old BOTOX. Hopefully, the |
| designated as A, B, C1, C2, D, E, F, and G. Seven are | | | | reduced protein load of the new BOTOX leads to |
| associated with paralysis. Types A, B, E and, rarely, F | | | | reduced immunogenicity and a lower incidence of |
| and G are associated with human botulism.The dose | | | | neutralizing antibody formation.Dysport is another |
| of botulinum toxin is expressed in mouse units. One | | | | formulation of botulinum toxin type A available in |
| unit is equal to the amount that will kill 50% of a | | | | Europe and a few other countries. It is prepared |
| group of 18- to 22-g Swiss Webster mice when | | | | using column-based purification techniques and |
| injected intraperitoneally. The human lethal dose (LD) | | | | distributed in 500-unit vials that can be stored at |
| for BOTOX (botulinum type A purified neurotoxin | | | | room temperature. BOTOX and Dysport are both |
| complex) is estimated at approximately 3000 units. | | | | botulinum toxin type A preparations but are quite |
| BOTOX injections of less than 100 units usually are | | | | distinct from one another. BOTOX is approximately 4 |
| used for cosmetic purposes and of less than 300-600 | | | | times more potent on a per unit basis, and Dysport |
| units for other purposes, thereby allowing a wide | | | | doses often are approximately 4 times the BOTOX |
| safety margin. Recognizing that doses are not | | | | doses used to generate a similar clinical effect. |
| interchangeable among different formulations of | | | | Differences in these toxins may relate to differences |
| botulinum toxin (BOTOX, Dysport, Myobloc) is | | | | in the strain of bacterium, preparation, diffusion, and |
| important; to achieve similar clinical effects, different | | | | potency testing.Myobloc is a botulinum toxin type B |
| doses are used.BOTOX is a sterile lyophilized form of | | | | preparation currently in clinical trials. It is anticipated |
| botulinum toxin type A. It is produced from a culture | | | | that it will be distributed as a solution. Little |
| of the Hall strain of C botulinum and purified by a | | | | information is available concerning the cosmetic use |
| series of acid precipitations to a crystalline complex | | | | of Dysport and Myobloc. The remainder of this article |
| containing the toxin and other proteins. The FDA | | | | therefore focuses on BOTOX, and all unit doses |
| approved BOTOX in December 1989 as an orphan | | | | refer to BOTOX unless otherwise specified. |