USP is the institute called United States Pharmacopeia, the 23 and 24 are standards, 24 is the current one instituted in 2000, they are updated every 5 years, the next one is going to be USP25 to come out in 2005 but will be available in july of 2004.
I dont know why i felt like answering this for you but you better think twice about knocking on me when i am the only one who can answer your questions.
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~The Recreational Pharmacist
Fuck Social, Screw you plur fucks, you dont need a forum for "ELMOvsTELLETUBBIES"
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