is fresh and cooled by ice from the pharmacy. I then freeze the rest. The next time I use it is fairly effective. After that it is close to useless. The pharmacist says it is only good for 28 days even with freezing. If it is no good after 28 days wouldn't that mean it is less and less effective or does it all just go bad at the 28 day mark. Does it really go bad that fast? I can't tell if my body is becoming immune to it's effects or the medicine is going bad that fast. I am 68 years old and the pharmacy has a minimum size prescription and there is no way I can use it all in 28 days. Is there a way to get the dry powder form and mix it yourself without using the pre-loaded syringes? They seem to be too expensive. I realize this is two or three questions but I appreciate your help.