Dysport & Botox Only Lasting a Month, Why Is That?

The effects of both Dysport and Botox should last 3-4 months.  If it is not lasting this long for you, I recommend that you see your provider to make sure that you are receiving an adequate dose. 

There are various reasons why Dysport or Botox might last a shorter period of time in some individuals. These reasons include injection technique issues, storing the product for a long period of time, improper dilution of the product, antibodies, individual metabolism, and inadequate units.
The most common reason would probably be using an inadequate number of units for the particular individual. Each individual is unique, and while many injectors have a relatively standard routine number of units for each product in a given area, some individuals may require more or less units.  
In most cases, the product (either Dysport or Botox) will last 3-4 months, not 6 months.
All the best,

Although there is some inherent variability in duration of effect, Botox and Dysport typically are expected to last 3-4 months. Much of this depends on getting the initial dose correct, which may require adjusting to each patient's response. It isn't clear what you are describing in terms of paying per month rather than by the actual dose. Zinc supplements might help get a better effect, though this hasn't been proven (we are doing a trial to see.)

  I agree that the duration of the effect of these agents are dose dependent.  Not all Crow's feet are the same and here in Florida I can see patients with VERY extensive (long) and deep rhytids (wrinkles).  I believe that most patients require AT LEAST 10-15 units per side depending of the severity of the problem.  So yes.  You might not be getting enough units injected.  This is something that only your doctor can answer.  Ask him and/or consider seeking out another provider.

Dysport and BOTOX last about 4 month max.  In my experience, if you have a spectacular result from these services, you will begin thinking about getting more treatment as soon as the maximum treatment effect begins to soften which is about 2 1/2 months.  When a service disappears faster than this, it is generally because not enough treatment was used to begin with.  BOTOX and Dysport are not bioequivalent and they are not biosimilar.  This means that your treating doctor has to experiment a bit to learn what dose to use with the Dysport to get a treatment effect that is similar to what you experience with BOTOX.  It is not as simple as applying a conversion factor and saying OK, she was good with 10 units of BOTOX so she needs 2.7X10=27 units of Dysport.  It is likely that your treating doctor in an abundance of caution did not use enough Dysport on your last treatment.

The most common reason for the Botox to not be lasting long enough is that too low a dose is being injected - the dosing depends on your age and strength of your particular muscles, and is best ascertained by a cosmetic expert such as a dermatologist or plastic surgeon. If you overuse muscles such as by smoking or through heavy weight lifting, Botox will also likely last less time. Botox typically lasts 3-4 months, with some patients getting 5-6 months duration. In a small percentage of patients, there are antibodies against Botox or Dysport which results in the Botox wearing out more quickly. You may also benefit from the addition of a filler in the treatment area.

The controllable factors that effect the duration of a neuromodulator such as Botox or Dysport are the strength of the solution, muscle density and accurate injection of the target muscle. I have found that the Dyport to Botox unit conversion is about 3 units of Dysport to 1 unit of Botox. I reconstitute both to the same effective strength with 2.5 cc of sterile normal saline (Botox comes in 100U vials and Dysport in 300 units) and that way I get the same effect from both. I do not see a difference in effectiveness between the two products with that dilution. I suggest using a 30 or 31g insulin needle on 0.5 or 0.3cc syring for the most comfortable and efficient injection. Also, the crows feet muscle is immediately under the skin and a small 2-3 unit injection bleb about 1-2 cm lateral to the orbital rim produces the most efficient injection. If the injection is too deep, much of the solution is dispersed and not picked up by the targetted muscle and the duration of effect may be shortened. I usually recommend 6-8 units of Botox or 18-24 units of Dysport per side for Crows feet treatment every 4 months. You can use a more concetrated solution but you have to be very careful with your injection depth and volume as it could cause ptosis or even incomplete eye closure. Also icing 5-10 minutes before and after the injections help keep the solution from being carried away from the targetted muscle by the dialated vessels in the immediate post-injection period thus decreasing the effective treatment dose and the duration of muscle relaxation. The icing also improves tolerance of the injection.

The mode of action is identical for both product . Both block muscle function. Every person is different and can get different results. Because of that I have had people who have had a 1-2 month effect while the usual is 4-6 months in my hands. I think the unit concentration is important. Also I have had better luck with botox then with dysport.  I have noticed that Dysport needs more units to get the same affect . 

The most common reason is the dose used was inadequate. However, you need to consider the dilution and exactly when the dilution was done...how long prior to your injection. Botox and Dysport are not equivalent, but the effect on SNAP 25 (the actual, action site) is the same. If the dose and dilution are correct, then there is the possibility that you have antibodies against the protein of the molecules. This is quite rare, but is possible if you have been exposed to the bacteria that produce the toxins. So first try higher, fresher doses. This will most commonly "fix" the problem.

In most instances, Botox usually lasts 3 to 4 months on average, while it may last up to 6 months in some patients. There are several reasons that the product may not last including:


 Too few Units were injected. For reference, on average 25 units are used for the frown lines. As different physicians use different dilutions (how they mix the product), 0.5cc from one physician may equal 25 units and 0.5cc from another may equal 15 units. Therefore, we meausre in units not cc or mL. The amount of units needed for an effect varies from person to person, and men often need more units per treatment area than woman.

Improper injection. The Botox may have been injected partially into a blood vessel or it did not get to the muscle where it acts because of poor injection technique or due to over-dilution of the product (more cc of saline used in a vial yielding fewer units per cc)

Partially inactivated/stored product. Botox is not incredibly stable and can be theortically inactivated by aggressive mixing, the longer it is stored, or if not refrigerated.

Antibodies. Some patients do make antibodies to the Botox toxin, which will negate the effects of the product. This is not common and may occur after many treatment sessions.

Bruising.  Teoretically, bruising (the collection of blood under the skin) can dilute the Botox or carry it away from where it need to act. This may lessen the overall effect of the product, although this is not typically seen and would be localized.


For most patients, the next step is to try again with a freshly mixed vial of Botox. If one has the same short effect, then more units would be tried.