Adult: For acute mild cases: Initially, 1 g daily in divided doses. Dose may be increased gradually over 1 week depending on patient's response, up to a Max of 3 g daily, if necessary. Max: 1 g per dose. Maintenance of remission: 500 mg bid. Dosage and treatment recommendations may vary between countries (refer to local product guidelines).
Administration
Olsalazine Should be taken with food.
Contraindications
Hypersensitivity to olsalazine or other salicylates.
Special Precautions
Patient with severe allergy or asthma, pre-existing skin conditions (e.g. atopic dermatitis and eczema). Patients taking nephrotoxic medications or with history of renal disease. Renal and hepatic impairment. Elderly. Pregnancy and lactation.
Adverse Reactions
Significant: Mesalazine-induced hypersensitivity reactions including internal organ involvement (e.g. hepatitis, myocarditis, pericarditis, nephritis, haematologic abnormalities, pneumonitis); mesalazine-induced acute intolerance syndrome (e.g. cramping, acute abdominal pain, bloody diarrhoea; occasionally fever, headache, rash); severe cutaneous adverse reactions (e.g. acute generalised exanthematous pustulosis, drug reaction with eosinophilia and systemic symptoms, Stevens-Johnson syndrome, toxic epidermal necrolysis); severe photosensitivity reactions (particularly in patients with pre-existing skin conditions); renal impairment (e.g. minimal change disease, acute and chronic interstitial nephritis, renal failure), nephrolithiasis. Rarely, serious blood dyscrasias. Cardiac disorders: Tachycardia. Gastrointestinal disorders: Diarrhoea, nausea, vomiting, dyspepsia, abdominal pain or cramps, stomatitis. Infections and infestations: URTI. Investigations: Increased hepatic enzyme. Musculoskeletal and connective tissue disorders: Arthralgia, myalgia. Nervous system disorders: Headache, dizziness, paraesthesia. Psychiatric disorders: Depression. Respiratory, thoracic and mediastinal disorders: Dyspnoea. Skin and subcutaneous tissue disorders: Rash, pruritus, urticaria, alopecia.
Avoid prolonged exposure to sunlight or UV light; wear protective clothing and use sunscreen when going outdoors. Maintain adequate fluid intake during treatment.
Monitoring Parameters
Monitor renal (before treatment initiation and periodically during therapy) and hepatic function; CBC (particularly in elderly). Assess for signs and symptoms of hypersensitivity reactions, worsening acute intolerance syndrome, and dermatologic toxicity.
Overdosage
Symptoms: Nausea, vomiting, abdominal pain, tachypnoea, hyperpnoea, tinnitus, neurologic symptoms (e.g. headache, dizziness, confusion, seizures). Severe intoxication may lead to electrolyte and blood pH imbalance, and may also cause damage to other organs (e.g. renal and liver). Management: Supportive treatment. May employ gastrointestinal tract decontamination to prevent further absorption. Administer appropriate IV therapy and maintain adequate renal function to correct fluid and electrolyte imbalance.
Drug Interactions
Increased risk of myelosuppression with azathioprine, tioguanine, and mercaptopurine. Increased risk of bleeding with LMWH or heparinoids. Increased prothrombin time with warfarin. Increased risk of nephrotoxicity with nephrotoxic drugs (e.g. NSAIDs). May increase the risk of developing Reye's syndrome when coadministered with varicella vaccine; avoid administration within 6 weeks of vaccination.
Lab Interference
May result in false elevation of urinary normetanephrine levels when measured using liquid chromatography with electrochemical detection.
Action
Description: Mechanism of Action: Olsalazine is a mesalazine (5-aminosalicylic acid) derivative. The exact mechanism of action of mesalazine has not been fully elucidated; however, it appears to exert its anti-inflammatory effect locally in the gastrointestinal tract. Mesalazine may reduce inflammation by inhibiting cyclooxygenase and lipoxygenase pathways in the colon, thereby blocking the mucosal production of arachidonic acid metabolites. Pharmacokinetics: Absorption: Very little portion is absorbed from the upper gastrointestinal tract. Time to peak plasma concentration: Approx 1 hour. Distribution: Enters breast milk (mesalazine). Plasma protein binding: >99%. Metabolism: Metabolised mainly in the colon by colonic bacteria into the active drug, mesalazine (5-aminosalicylic acid); mesalazine undergoes rapid N-acetylation to form N-acetyl-5-aminosalicylic acid. Excretion: Mainly via faeces; urine (as mesalazine [approx 20%, mainly as N-acetyl-5-aminosalicylic acid]; <1% as olsalazine). Elimination half-life: 54 minutes.
Chemical Structure
Olsalazine Source: National Center for Biotechnology Information. PubChem Compound Summary for CID 22419, Olsalazine. https://pubchem.ncbi.nlm.nih.gov/compound/Olsalazine. Accessed Nov. 25, 2024.