Single Dose pharmaceutical preparations do not require a preservative unlike multidose preparations?

Question

Does any one know of a good source that explains why this is the case?

thanks

Answer 1

I do not know of a good source, but I can explain this very easily.

It is very logical, think about it

If you use a multidose preparation, you are opening and closing the vial on several occasions. The very second you open anything, pathogenic organisms WILL enter. Virus, bacteria and other organisms drift about in the air on dust particles or even by themselves since they are small and do not have a high mass. The pathogens will enter into the vial, so you must added a preservative that will kill them, the last thing you need is a lethal septic shock from taking an injection from a vial! The less mass a substance has, the longer it takes for it to sediment out of the air. Single dose preparation are ONLY used once and until they are actually used they are sealed in a sterile vial, once the vial is opened and used, it is discarded after and you do not reseal it. Then what is the sense of adding a preservative, nothing. In fact, it is much better to use single dose vial because you do not have to reseal it and can just through it away after opening it.