Botox and Dysport: Is there a dose conversion ratio in dermatology and aesthetic medicine?

Field effect of two commercial preparations of botulinum toxin type A: A prospective, double-blind, randomized clinical trial

“…Other articles indicated higher ''diffusion'' of ABO 13,14 when using a higher dose equivalence of 3:1. Karsai et al 15,16 suggested that this is simply a dose effect as opposed to the claim that one product ''diffuses'' more than the other. The current study also supports the assertion that higher doses of BoNTA are relevant in producing a greater FAE and FME.…”

“…The assay method used to test ABO is more sensitive than the assay used for ONA, resulting in different potencies per unit in both formulations. 12,15,27 Hambleton and Pickett 27 measured different samples of ABO and ONA using the two different assay methods used by the companies at that time. Their results showed that there was an approximate 3:1 ratio; that is, 1 U of ONA was equivalent to approximately 3 U of ABO.…”

Botulinum toxin type A for aging face and aesthetic uses

“…Other studies also showed that the dose equivalences of 1 : 2 to 1 : 2.5 (between BOTOX ® and DYSPORT ® ) have similar results regarding efficacy, intensity, and duration of the paralysis or anhydrosis, and safety (Table 1) (22–24). According to Karsai and Raulin, the dose equivalence of 1 : 2.5 U between BOTOX ® and DYSPORT ® is adequate (25).…”

Efficacy of Onabotulinum Toxin A (Botox) versus Abobotulinum Toxin A (Dysport) Using a Conversion Factor (1 : 2.5) in Treatment of Primary Palmar Hyperhidrosis

“…Today, many clinicians use a 1 : 3 conversion factor [4, 16]. However, several authors suggested that such ratios may be high and there was a consistent trend in most of those studies for Dysport treatment to have more adverse events and longer lasting effects [17]. One publication placed the conversion ratio at 1 : 1.3–1.6 and reported that both preparations were similar in the efficacy and in the diffusion characteristics [4].…”

“…Others suggested that ratios as 1 : 2.5 may be more accurate [18]. Additionally, in Germany, the manufacturers recommend the Botox: Dysport conversion ratio to be 1 : 2.5 and in Austria, both products are registered for the treatment of axillary hyperhidrosis, with an initial dose of 50 U Botox or 100 U Dysport (i.e., a ratio of 1 : 2) [17]. Accordingly, in the current work, we decided to use a conversion factor between Botox and Dysport of 1 : 2.5 U in treating PPH and to study the efficacy of this ratio in bringing out the desirable effect with a less potential than doses with ratios 1 : 4 and 1 : 3.…”