Forgive me knock, I wasn't entirely clear. As I say in my post, it can be useful, obviously, if the BAs or every likely ROA are known, in weighing up the best way to get the most out of a drug. BA, though, isn't an independent measure, it only makes sense in the context of a specific ROA (so you can talk about the oral BA, the inhaled BA), but not just of BA in and of itself, with no qualifier. Am I making sense? 5-EAPB will have an oral BA, a rectal BA, but not just a BA, I if you get me? I wasn't trying to denigrate the concept itself, it was just the way the poster to whom I was responded indicated to me through their post that they hadn't quite grasped the concept of bioavilability, which is relative, and so only makes sense when you have a particular ROA, and you're comparing it to IV (which is, definitionally, always 100 per cent. They seemed to be asking for an "absolute BA", and I was trying to explain why that wasn't really something that could be usefully asked. I was really speaking to that poster alone, I hope so that they might get a firmer grip on the concepts they were thinking about. If "what is the oral BA of 5-EAPB", then I still wouldn't have known, and suspect no-one knows (you have to do experiments with rats and stuff, and I don't think 5-EAPB has been the target of much research), but I would at least have known what the question meant. I didn't express it clearly before (I was half a bottle of gin and 6mg etiz down), but I hope I've explained what I was saying more lucidly now.
's me drugs and I 
