Many practitioners are having to change their toxin brand from Azzalure to Botox (or Bocouture) due to a current shortage. This is causing a lot of confusion and panic in the industry.
It is a well known fact in the aesthetics industry that the strength of Azzalure (also known as Dysport) and Botox (by Allergan) or Bocouture (also known as Xeomin) is measured in different units. Azzalure is measured in Speywood units, Botox/Bocouture is measured in Botox units. It's like two different languages. Injectors who solely use Azzalure are sometimes unable to 'speak' Botox, and similarly, some injectors who solely use Botox/Bocouture are unable to 'speak' Speywood. Of course, there are also injectors who are 'bi-lingual'.
Additionally, you have injectors who record their toxin doses in insulin units. Often, insulin users don't 'speak' Speywood or Botox units.
As toxin is not insulin, measuring in an insulin unit is simply recording how much fluid you have injected per site using an insulin syringe. Many injectors don't realise that iu is just a way of recording liquid dose. Many do not realise that it's closely related to ml. If you add 0.63ml of saline to your Azzalure, it will give you 63iu in the vial. All you need to do to find insulin units is remove the decimal point from your ml amount (and ensure that your ml amount is written to 2 decimal places). E.g. if you are injecting 0.05ml, remove the decimal point and that's 5iu. If you are injecting 0.1ml, ensure you are thinking of it to 2 decimal places (so 0.10ml) and remove the decimal point - 10iu. If you are adding 1.25ml to your toxin vial to reconstitute, remove the decimal point and you will realise you have 125iu in that vial now.
Botox and Bocouture use the same units and dilutions, so this guide can be used for either product. The difference between the two is, Bocouture is low protein and does not need to be refrigerated until AFTER dilution. It is a good choice for people who do not respond well to high protein toxin. It is cheaper than Botox but a lot of practitioners feel it does not last quite as long. Botox is a high protein toxin, it must be refrigerated in the same way as Azzalure (even when not reconstituted). It is long lasting but much more expensive.
I have created this post to explain how Azzalure injectors can easily get their head around the switch to Botox. I have included examples for both Speywood unit users and insulin unit users. It is very detailed for those of you who want to understand exactly why these are the conversions, but I have added a simple summary at the end for those who feel a bit overwhelmed by all of the numbers.
The first thing to be aware of is that a 125 unit vial of Azzalure is the equivalent strength to a 50 unit vial of Botox/Bocouture. So if you usually use 125 units Azzalure for your client, you will need to order a 50 unit vial of Botox for them instead. If you usually order a double vial of Azzalure, and dip into that second vial on review appointments/top-ups, then you will need to order a 100 unit vial of Botox (or a 2 pack of 50 unit vials).
The next part I have broken down into advice for either Speywood injectors or Insulin injectors. Read the advice for whichever unit you 'speak' in/record your doses in.
For injectors that use SPEYWOOD units
As a 50 (Botox) unit vial of Botox/Bocouture is equivalent to a 125 (Speywood) unit vial of Azzalure, this means that every 1 Botox unit is worth 2.5 Speywood units. You can easily prove this by dividing 125 by 50. 50 goes into 125 2.5 times. So considering these vials are ultimately the same strength, this must mean that, for every 1 Botox unit in a vial, there are 2.5 Speywood units. If you usually work in Speywood units all you need to do to find your equivalent Botox dose is to divide your Speywood dose by 2.5 (e.g. you usually inject 10 Speywood units - so you will now need to inject 4 Botox units (10/2.5 = 4) . However, if you aren't sure how much fluid you need to inject to create those Botox doses, move on to the next bullet point.
How much fluid you add to your vials is essential information to your conversions. Botox/Bocouture is usually diluted with 1ml or 1.25ml per 50 unit vial (if getting double the units in a vial, you will need to double the fluid added - so 100 unit vials needs 2-2.5ml dilution). Azzalure is usually diluted with 0.63ml per 125 unit vial. To find how much fluid you need to inject to get a certain Speywood or Botox unit dose, use this simple calculation: What you want to inject x What you have diluted with, then divide that by the number of units in the vial. E.g. I want to inject 4 Botox units, I have diluted with 1.25mls, I have 50 units in my vial 4 x 1.25 / 50 = 0.1ml. So you have to inject 0.1ml (or 10iu) to inject 4 Botox units. An example in Speywood would be 'I want 10 Speywood units, I have diluted with 0.63ml, I have 125 units in my vial. 10 x 0.63 / 125 = 0.05ml (to 2 decimal places) (5iu). Please note, this calculation cannot be used without a desired Botox or Speywood dose. You cannot enter an iu amount as the first number.
For injectors that use INSULIN units
I have different advice depending on how much saline you usually reconstitute your Azzalure with. As insulin dosage will change depending on the amount of fluid put into the vial.
My recommendation to those who usually use insulin units and dilute their Azzalure with 0.63mls is to use 1.25mls when reconstituting 50 units of Botox or Bocouture - it makes for a very simple conversion as you can just double your insulin units when using this dilution of Botox to get the same strength dose. If you usually inject 3iu of Azzalure per point, just dilute your 50 units Botox with 1.25ml, and inject 6iu to get the same strength dose. Easy! You will make things a bit more complicated for yourself if you try to change the dilution of your Botox to 1ml as it changes the math and can no longer just be doubled (3iu Azzalure would be 4.8iu Botox, and 5iu Azzalure would be 8iu Botox) it has to be multiplied by 1.6 - which is just harder math than necessary.
The reason that so many injectors that use insulin units get confused switching between toxins is they get bogged down with the difference between Speywood and Botox units. If you are using insulin units, you do NOT need to care about Speywood and Botox units. You are injecting based on fluid amount, not on toxin strength. It does not matter how much stronger a Botox unit is than a Speywood unit. Forget it. Forget that one vial has 125 units and one has 50 units. All you need to know is that the toxin contained in them is the same strength. You essentially have 2 vials of equal strength. All that is going to change is how much fluid you are putting in each. If you put 0.63mls in a vial of Azzalure, and 1.25mls in a vial of Botox - you have doubled (just about) the fluid. Therefore, to get the same strength dose as Azzalure, you must inject double the amount of Botox you are injecting (because the toxin in the vial is dissolved in twice as many insulin units). It's really that easy. Unit strength (Speywood and Botox) means nothing if YOU aren't measuring in them. You are measuring in fluid (iu) so you only need to care about the difference between the amount of fluid in those vials. If you double the fluid in the vial, you need to double the insulin units you inject.
Therefore, if you are an injector who dilutes their Azzalure with 1.25mls (or any amount around 1ml), and you use insulin units - JUST DILUTE THE BOTOX/BOCOUTURE WITH THE SAME AMOUNT AND INJECT YOUR USUAL NUMBER OF INSULIN UNITS. Remember, the strength in the vials are identical (even though one is 125 Speywood units and one is 50 Botox units - think of it like 2.54cm and 1 inch - they still measure exactly the same as a whole, even though they are different numbers), and insulin units are only a measure of fluid. So if you have the same strength in total in the vials, and you have put the same amount of fluid in both - you will have the same number of insulin units in the same whole vial. Nothing has changed (except the label on the vial), so 5iu remains 5iu. You would think this would be a much simpler way to always inject toxin, but we can't really advise mixing Botox with 0.63mls as Azzalure is usually mixed, because its a very concentrated dose. As Botox/Bocouture does not spread as far as Azzalure, you would possibly have some problems getting full coverage of areas like the Frontalis with such small deposits of fluid as you would inject Azzalure.
You don't really need to know this, because you are not concerning yourself with Botox and Speywood units, but it is useful to learn how the conversions work in case you ever want to understand the strengths. If Botox is diluted with 1.25mls, this makes for 2 Botox units per 5iu, and 4 Botox units per 10iu. As previously discussed, 2 Botox units is equivalent to 5 Speywood units (2 Botox units x 2.5 = 5 Speywood units). 2 Botox units is 5iu and 5 Speywood units is 2.5iu. So that means insulin units of Botox at this dilution is exactly double the insulin units of Azzalure at a dilution of 0.63mls. The math confirms it.
Diffusion of Azzalure vs Botox/Bocouture
Azzalure particles are said to spread around 2cm, whereas Botox/Bocouture particles are said to spread around 1-1.5cm. This is why we usually dilute Azzalure with half the amount of fluid that we reconstitute other toxins with - we are controlling how much it can spread out. Injectors who dilute Azzalure with 1.25mls are taking a risk of unwanted diffusion, and it does make critical areas like the corrugators a bit more risky to treat with increased amounts of fluid - as you need to inject more fluid than someone who reconstitutes with 0.63mls, to get the same dose.
A question I have seen asked a lot is 'do I need to put more injection sites now that I am switching to Botox/Bocouture?' The answer is; possibly. I would advise you not to, while you are getting used to the product. If you are matching the strength dose (using any of the options above) then adding more points would mean adding more toxin than you are used to - which I would not advise. Instead, I would recommend keeping to your usual style of injecting and usual doses. If you find, after a few clients, that you are not getting the diffusion you are used to, reduce the dose slightly per injection site, and add in a few extra sites to get a bit more coverage. E.g. if your usual mapping would have you converting to injections of 6iu of Botox in 5 Frontalis sites (30iu total) and its not giving you the same smooth coverage, consider injecting 3iu of Botox in 10 sites (or even 4iu in 5 sites plus 5iu in 2 sites, so you are still getting a 30iu dose).
(For Speywood injectors) - To account for reduced spread, some injectors who usually use Speywood units may choose (instead of using the true calculation of Speywood/2.5 = Botox) to simply halve their Speywood units to decide how many Botox units to inject (so instead of 10 Speywood/2.5 = 4 Botox, they would do 10 Speywood/2 = 5 Botox). This is not the true equation, as will give a slightly higher dose than the equivalent of what they normally inject with Azzalure, but is often done to compensate for the slight reduction in diffusion when using Botox/Bocouture. I would not advise to use this method until you have some familiarity of using your new toxin, and you understand how it behaves. However, if you find that you are struggling to get the same coverage with Botox when switching from Azzalure, this is an alternative method that you can try.
(For Insulin injectors) - If you are an insulin unit user, and you usually dilute your Azzalure with 0.63mls, the equivalent of this technique would be to dilute your Botox/Bocouture with 1ml (instead of the advised 1.25mls) and instead of multiplying your insulin units by the true value (1.6 for 1ml dilutions), continue to multiply your insulin units by 2 (the same as you would for a 1.25ml dilution) and this will give you slightly higher dosage per injection site. Again, I really do not recommend this until you have some familiarity with the new toxin.
Summary
In simple terms, the easiest way to switch to Botox from Azzalure is to simply dilute your 50 units Botox/Bocouture with 1.25mls and double the amount of insulin units you would usually inject (e.g. 4iu Azzalure = 8iu Botox). This works if you were previously diluting your Azzalure with 0.63mls (or near enough).
If you diluted your Azzalure with 1ml or more, simply reconstitute you Botox with an identical amount, and inject exactly the same amount of insulin units as you usually would. (These are the injectors who are the most likely to see a difference in spread (because they are still injecting identical amounts of fluid, but now using a toxin that spreads less. They may need to lower their dose per site slightly and add in more sites to make up for it and spread the product about a bit more).
If you are a Speywood unit user, simply divide Speywood units by 2.5 to find the equivalent Botox units. You can use the dosage finder equation (detailed above) to work out how much fluid this means you need to inject.
Don't change everything about your injecting. Don't look for new 'patterns' for Botox. Too much change is risky. Just work with your new toxin in the way you are used to for now, and make small changes as your confidence with the new brand grows and until you get a feel for how it acts.
Further Training
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