Olsalazine

Indications

Olsalazine is used for: Ulcerative colitis

Adult Dose

Oral Ulcerative colitis Adult: Acute mild cases: Initially, 1 g daily in divided doses, gradually increased over 1 wk, according to patient's response. Max: 3 g daily in divided doses (max/dose: 1 g). Remission maintenance: 500 mg bid. Max Dosage:

Child Dose

Renal Dose

Administration

Should be taken with food.

Contra Indications

Hypersensitivity to olsalazine or other salicylates.

Precautions

Patient w/ asthma, severe allergies. Renal and hepatic impairment. Pregnancy and lactation. Patient Counselling This drug may cause dizziness and/or blurred vision, if affected, do not drive or operate machinery. Monitoring Parameters Monitor renal function (e.g. serum creatinine, BUN, urinalysis) prior and during treatment (every 3 mth for 1 yr, then every 6 mth for next 4 yr, then annually thereafter). Monitor CBC, LFT, stool frequency.

Pregnancy-Lactation

Pregnancy Category: C Lactation Not known whether drug distributed into breast milk, use caution 5-ASA is excreted in breast milk & may cause diarrhea in infant However little is absorbed from oral olsalazine Avoid

Interactions

Increased risk of bleeding (e.g. haematoma) w/ LMWH or heparinoids. Increased prothrombin time w/ warfarin. Increased risk of myelosuppression w/ 6-mercaptopurine and thioguanine. Increased risk of developing Reye's syndrome w/ varicella vaccine, avoid admin w/in 6 wk of vaccination.

Side Effects

Side effects of Olsalazine : >10% Diarrhea (17%) Abdominal pain (11%) 1-10% Nausea/vomiting (6%) Headache (5%) Arthralgia (4%) Dyspepsia (4%) Joint pain (4%) Rash/itching (3.6%) Fatigue (1.8%) Bloating (1.5%) Depression (1.5%) Upper respiratory infection (1.5%) Anorexia (1.3%) Dizziness (1%)

Mode of Action

Olsalazine is a mesalazine [5-aminosalicylic acid (5-ASA)] derivative. The exact mechanism of action is still unknown but is thought to diminish inflammation by blocking cyclooxygenase and lipoxygenase pathways thus inhibiting the production of prostaglandin and leukotrienes in the colon; action appears to be topical rather than systemic.