Mesalazine preparations for the treatment of ulcerative colitis: Are all created equal?

Table 1 Summary of drug delivery mechanisms

Formulations	Generic name	Proprietary names	Mode of delivery	Site of drug release
Azo-bonded prodrugs	Sulfasalazine	Azulfidine®; Salazopyrin®; Pyralin®	Mesalazine bound to sulfapyridine	Colon
	Olsalazine	Dipentum®	Two mesalazine molecules bound together	Colon
	Balsalazide	Colazide®; Colazal®	Mesalazine bound to 4-aminobenzoyl-β-alanine	Colon
pH dependent	Mesalazine	Asacol®; Mesren®	Eudragit-S coating (dissolves at pH ≥ 7)	Terminal ileum, colon
		Salofalk®; Mesasal®; Claversal®	Eudragit-L coating (dissolves at pH ≥ 6)	Mid ileum to colon
		Salofalk Granules®	Eudragit-L coating and matrix core	Mid ileum to colon
Time dependent	Mesalazine	Pentasa®, Pentasa® granules	Microspheres encapsulated within an ethycellulose semi-permeable membrane	Duodenum to colon
MMX	MMX mesalazine	Lialda®; Mezavant XL®; Mezavant®	Enteric coating (dissolves at pH ≥ 7). MMX of lipophilic and hydrophilic excipients	Terminal ileum and entire colon

MMX: Multi-matrix system.