Brands, Medical Use, Clinical Data
- Anti-Inflammatory Agents, Non-Steroidal
- Rectal suppository (500 mg or 1000 mg)
Brands / Synonyms
Apriso; Asacol; Asacol HD; Asacolitin; Canasa; Claversal; Fisalamine; Lialda; Lixacol; m-Aminosalicylic acid; Mesalazine; Mesasal; p-Aminosalicylsaeure
; Pentasa; Rowasa; Salofalk
For the treatment of active ulcerative proctitis.
Sulfasalazine has been used in the treatment of ulcerative colitis for over 55 years. It is split by bacterial action in the colon into sulfapyridine (SP) and mesalamine (5-ASA). It is thought that the mesalamine component only is therapeutically active in ulcerative colitis.
Mechanism of Action
Although the mechanism of action of mesalamine (and sulfasalazine) is not fully understood, it appears to be topical rather than systemic. Mucosal production of arachidonic acid metabolites, both through the cyclooxygenase pathways, i.e., prostanoids, and through the lipoxygenase pathways, i.e., leukotrienes and hydroxyeicosatetraenoic acids, is increased in patients with chronic inflammatory bowel disease, and it is possible that mesalamine diminishes inflammation by blocking cyclooxygenase and inhibiting prostaglandin production in the colon.
20 to 30% absorbed following oral administration. 10 to 35% absorbed from the colon (rectal suppository) - extent of absorption is determined by the length of time the drug is retained in the colon.
Oral, mouse: LD50 = 3370 mg/kg; Oral, rat: LD50 = 2800 mg/kg; Skin, rabbit: LD50 = >5 gm/kg. There have been no documented reports of serious toxicity in man resulting from massive overdosing with mesalamine. Under ordinary circumstances, mesalamine absorption from the colon is limited.
Biotrnasformation / Drug Metabolism
Rapidly and extensively metabolized, mainly to N-acetyl-5-ASA (Ac-5-ASA) in the intestinal mucosal wall and the liver. Ac-5-ASA is further acetylated (deactivated) in at least 2 sites, the colonic epithelium and the liver.
CANASA® 500 mg and 1000 mg Suppositories are contraindicated in patients who have demonstrated
hypersensitivity to mesalamine (5-aminosalicylic acid) or to the suppository vehicle [saturated vegetable fatty acid
esters (Hard Fat, NF)], or to salicylates (including aspirin).
No information provided.