- Joined
- Dec 2, 2006
- Messages
- 431
- Reaction score
- 0
what are the differences between them? and are there any more? Are some of them equivalent?
what are the differences between them? and are there any more? Are some of them equivalent?
I can also think of CD, XR, CR, XE.and are there any more?
They all mean the same thing and different things.
It's like Confucius or something...
yes - there are more - extentabs, lontabs, etc....These are trademarked abbreviations & are descriptive of that product only. Be careful - one company can use SR for one thing and another company willl use ER for the same thing.
I can also think of CD, XR, CR, XE.
This is fascinating. I do remember while studying for my technician's license that there were ratings for generic drugs- I remember Synthroid, Levothroid, Levothyroxine were only slight analogs. Maybe it has something to do with the enantiomersim of the drug (ie Levo, left polaring..Not even 100% sure if you can translate this literally). Anyhow, can someone post the information that expalins the difference between ratings for generics and bioequivalencies? That would be good to brush up on right now.
These 3 aren't analogs...they are all the same exact chemical. Synthroid and Levothroid are just brand names of levothyroxine...they are all stereochemically levo because that's the biological active form, even if Synthroid hasn't incorporated that into the brand name. They're not all AB rated, not because of the chemical structure itself, but because of variable and erratic bioavailability. I think this is mainly because some products vary more in actual drug contration from batch to batch than others do, and since the relationship between free levothyroxine and TSH isn't linear, we want as tight of control as possible.I remember Synthroid, Levothroid, Levothyroxine were only slight analogs. Maybe it has something to do with the enantiomersim of the drug (ie Levo, left polaring..Not even 100% sure if you can translate this literally).