Based on the literature, it is not clear that there is any need to give melamine more than once a day; this is often in contrast to labeling for many of these products:

1. Inflamm Bowel Dis 2012; 18: 1785-94 
2. Inflamm Bowel Dis 2012; 18: 1885-93

The 1st study identified 11 relevant randomized studies, after excluding 6870 that were considered irrelevant. Five of these studies were single blind and one was open-label; the remainder were double-blind randomized trials. In total, these studies examined 4070 patients.

Mesalamine products studied: Mesalazine (Salofalk), MMX mesalamine, Asacol, and Pentasa

Summary of findings:

• Failure to induce clinical remission: relative risk (RR) with once daily 0.95; absolute risk 421 per 1000 in once daily group
• Failure to induce clinical improvement: RR 0.87; absolute risk 398 per 1000
• Failure to maintain clinical remission at 12 months: RR 0.92; absolute risk 286 per 1000
• Failure to adhere to study medication regimen: RR 1.21; absolute risk 128 per 1000

Thus, this meta-analysis indicates that once daily dosing is as effective as conventional dosing for both induction and maintenance, at least with the formulations that were tested. Also, in this meta-analysis, adherence was not improved with once daily therapy, though some previous studies have indicated that once daily therapy may be helpful particularly in the first few months of treatment.

The 2nd study examined 213 patients for maintenance of UC remission; patients were randomized to receive either Asacol 2.4 g once a day (QD) or 800 mg three times a day (TID). Patients were treated at 32 UK centers and had an average age of 50 years. Relapse rates were 31% for QD therapy and 45% for TID over 1 year.  This study showed that QD was noninferior to TID and possibly superior, perhaps due to improved adherence.

Perhaps it is time to give all mesalamine products once a day.