Drug Groups

approved

Description

Olsalazine is an anti-inflammatory drug used in the treatment of Inflammatory Bowel Disease and Ulcerative Colitis. Olsalazine is a derivative of salicylic acid. Inactive by itself (it is a prodrug), it is converted by the bacteria in the colon to mesalamine. Mesalamine works as an anti-inflammatory agent in treating inflammatory diseases of the intestines.

Indication

For the treatment of Inflammatory Bowel Disease and Ulcerative Colitis.

Pharmacology

Olsalazine is an anti-inflammatory drug used in the treatment of Inflammatory Bowel Disease and Ulcerative Colitis. Olsalazine reduces the bowel inflammation, diarrhea (stool frequency), rectal bleeding, and abdominal pain. Like Balsalazide, Olsalazine is believed to deliver Mesalazine, or 5-aminosalicylic acid (5-ASA), past the small intestine, directly to the large intestine, which is that active site of disease in ulcerative colitis.

Toxicity

Maximum single oral doses of 5g/kg in mice and rats and 2 g/kg in dogs were not lethal.

Affected Organisms

Biotransformation

Most (98 to 99%) of an oral dose is rapidly converted into two molecules of 5-aminosalicylic acid (5-ASA) by colonic bacteria and the low prevailing redox potential found in this environment. The conversion of olsalazine to mesalamine in the colon is similar to that of sulfasalazine, which is converted into sulfapyridine and mesalamine. Approximately 0.1% of an oral dose of olsalazine is metabolized in the liver to olsalazine-O-sulfate (olsalazine-S)

Absorption

After oral administration, olsalazine, has limited systemic bioavailability. 98-99% of the dose is converted to mesalamine (5-ASA) in the colon, which is absorbed slowly resulting in very high local concentrations in the colon.

Half Life

Olsalazine has an elimination half-life of 0.9 hours, however, olsalazine-S has a half-life of 7 days.

Protein Binding

Olsalazine and olsalazine-S are more than 99% bound to plasma proteins. Mesalamine (5-ASA) is 74% bound to plasma proteins.

Elimination

Approximately 0.1% of an oral dose of olsalazine is metabolized in the liver to olsalazine-O-sulfate (olsalazine-S).The remaining 5-ASA is partially acetylated and is excreted in the feces.

External Links