Just found out about
According to this post
:"The main difference between the two medicines is the size of the dosage. Asacol is taken in 400 mg doses with a maximum of 2.4 g/day. Asacol HD is taken in 800 mg doses with a maximum of 4.8 g/day. So the new version of Asacol is simply double the dose of the old medicine.
The press information on Asacol HD make clear that one HD tablet is not bioequivalent to two Asacold tablets. In test results of Asacol HD, patients with moderate colitis showed a more positive response to the HD version of the drug after six weeks than to the mild version of the drug."
I'd never heard the max dose of Asacol is 2.4 g/day, and I know I've seen posts here by people taking more than that.
Official press release (which doesn't mention Crohn's at all):www.prnewswire.com/cgi-bin/stories.pl?ACCT=109&STORY=/www/story/07-07-2009/0005055609&EDATE=