What Happens to Left over Botox?

Botox or Dysport is typically $300-350 per area for 1 area, $500-600 for 2 areas and $675-800 for 3 areas (glabella or frown area, lateral canthi or smile creases on the sides of the eyes, and the 3rd area is the forehead). Many docs sell Botox by the areas so you know what you have to spend to cover the area appropriately.

If you visit a busy practitioner, it is highly unlikely that he/she will have any "Leftover" botox. You have to realize that you are not purchasing the vial, you are purchasing the amount of units you used. IF you were paying for the entire vial, it would be a minimum of $900 ($9 per unit is usually the lowest) and up to $1500 ($15 per unit).

Jill
I take it you are asking if you pay for two areas of BOTOX and there is left over in the syringe what happens to the left over BOTOX?
In a proficient practice this would be an unheard of event. However, supposing the recommended more BOTOX than you needed, whatever is in the syringe used to treated you should be disposed of as a hazardous waste. Using left over product drawn up an partially used on one person should never be used on anyone else. The reason for this is that it is possible for have crosscontamination from one person to a next following this type of practice. For this reason if for some reason not all of the BOTOX you paid for is used in your treatment it is wasted, fancy doctor talk for throwing it out.
As a practical matter, an experienced practice should be able to tell you exactly how much BOTOX you need and all of it should be used to treat you. So this type of situation should never arise.

In our busy cosmetic practice, each patient's amount of Botox needed for their treatment is drawn, in a sterile fashion, out of the Botox vial. If there's not enough units left in that vial, a new one is opened to add to that volume. The Botox treatments are so numerous per week that one bottle doesn't last long at all. The cost of Botox varies based on the number of units used, the location on the face or body (some require more skill and technique), the physician and the geographic area. Each area is usually several hundred dollars and may last four to five months, possibly less.

Many years ago, Botox was reconstituted and used in one day. We were told by the company and the FDA that it was only good for that day so we would gather up all our Botox patients and inject all of them one day a week or month. Any leftover was either discarded, given to the last patient or used on a staff member. Since them we have found that Botox is good for weeks once it is reconstituted from the freeze dried for4m it comes in.
As for pricing, most doctors charge by the unit, some by the region. Prices vary from city to city. Prices also vary according to skill and experience. You can surely get discount Botox from someone who just finished a weekend course and is looking to build a Botox practice. But do you want someone learning on you? Like all of cosmetic surgery, if you want quality results it may cost more.

In general two areas would require about 40 units. Or around five hundred dollars. The remaining units can be used for another area, however there probably would be additional fees associated with the service as well.

Every doctor doe sit a bit differently. I charge patients for the areas treated.  I do not usually have "left over" for over things unless the patient pays for it.

You are charged by the amout of Botox used for your treatment. The "left over" botox is used for other patients who pay for their treatment. It comes in a multiple dose vial. We do not throw any of it away.

I agree with Dr. Rand's comments. The vast majority of Plastic surgeons and Dermatologist charge per units and use the amount of Botox we plan on using. As a result, you do NOT pay for Botox that is not used.
Dr. P. Aldea

Interestingly, according to the package insert, BOTOX (and its sister Dysport) come as single use vials. However, except for its use for hyperhidrosis (excess sweating), nearly all physicians use a single vial for multiple patients. Thus, there would not be any extra remaining which is dedicated for your use.
Vials contain 100 units. Sometimes, two patients might use that vial of 100 units (say two males, who require more BOTOX due to stronger facial muscle structure) and sometimes 3-5 patients, especially if "touch-ups" are involved.
As far as pricing, some physicians charge by the unit and others by the area. Judging by your name, you are female, and would benefit more by being charged by the unit. Men, requiring more units, make out better if they are charged by the area. As has been answered on Real Self before unit price varies considerably. I have heard patients being charged as much as $21/unit and as little as $8/unit.