5 Aminosalicylic Acid (Mesalamine)


5 Aminosalicylic Acid (Mesalamine) is used for: Ulcerative colitis, Ulcerative proctitis, Crohn's Disease.

Adult Dose

For the treatment of mildly to moderately active ulcerative colitis: The usual dosage in adults is two 400 mg tablets to be taken three times a day for a total daily dose of 2.4 grams for a duration of 6 weeks. For the maintenance of remission of ulcerative colitis: The recommended dosage in adults is 1.6 grams daily, in divided doses. Treatment duration in the prospective, well-controlled trial was 6 months. Crohn`s disease: 800 mg 3 times daily. Hepatic impairment: Avoid in severe impairment.

Child Dose

Ulcerative colitis: Dose is dependent on preparation and brand used. Tablets: 5-15 yr: Acute attack: 15-20 mg/kg (max: 1 g) tid; maintenance of remission: 10 mg/kg (max: 500 mg) 2-3 times daily.

Renal Dose

Renal impairment: CrCl (ml/min) <20 Avoid.


May take with or without food.

Contra Indications

Hypersensitivity to salicylates, aminosalicylates, or any component of the product.- Severe renal impairment (GFR less than 30 mL per minute).- Severe liver impairment.- Gastric and duodenal ulcers- Children under the age of 2 years


Mild to moderate impaired renal or hepatic function (test serum creatinine before treatment, every 3 mth for 1st yr, every 6 mth for next 4 yr, then annually). Elderly; active peptic ulcer; pregnancy, lactation; patients predisposed to pericarditis or myocariditis. Counsel patients to report any unexplained bleeding, bruising, purpura, sore throat, fever or malaise during treatment; perform blood count and stop treatment if blood dyscrasias suspected. Counsel patients taking delayed release tablets to report repeatedly unbroken or partially broken tablets in their faeces. Pyloric stenosis may delay release into colon.Patients with pulmonary disease, in particular asthma, should be very carefully monitored during a course of treatment.Hypersensitivity to Sulphasalazine.In patients with a history of hypersensitivity to sulphasalazine, therapy should be initiated only under close medical supervision. Treatment must be stopped immediately if acute symptoms of intolerance occur such as abdominal cramps, acute abdominal pain, fever, severe headache and rash.Paediatric populationThere is only limited documentation for an effect in children (age 6-18 years). Lactation: Not known whether drug or metabolites are distributed into breast milk; use caution.


Pregnancy: Limited published data on mesalamine use in pregnant women are insufficient to inform a drug-associated risk; no evidence of teratogenicity was observed in rats or rabbits when treated during gestation with orally administered mesalamine at doses greater than the recommended human intra-rectal dose Lactation: Developmental and health benefits of breastfeeding should be considered along with mother’s clinical need for therapy and any potential adverse effects on the breastfed child from therapy or from underlying maternal conditions; mesalamine and its N-acetyl metabolite are present in human milk in undetectable to small amounts; there are limited reports of diarrhea in breastfed infants; there is no information on effects of drug on milk production; monitor breastfed infants for diarrhea


Do not give with lactulose or other drugs which lower pH for they prevent release of mesalazine. May decrease digoxin absorption.

Adverse Effects

Side effects of 5 Aminosalicylic Acid (Mesalamine) : 1-10% Abdominal pain (4-8%) GI discomfort (4-8%) Headache (7%) Flatulence (1-6%) Nausea (1-6%) Fatigue (3%) Asthenia (3%) Malaise (3%) Weakness (3%) Fever (3%) Exacerbation of colitis (3%) Dizziness (2-3%) Rash (1-3%) Pruritus (1-3%) Acne (1-3%) Frequency Not Defined Pericarditis (rare) Pharyngitis Sensitivity reaction Cholestatic hepatitis Creatinine clearance decreased Flu like syndrome Discolored urine Renal Impairment Mesalamine-induced acute intolerance syndrome Hypersensitivity reactions Hepatic failure

Mechanism of Action

Anti-inflammatory agent; mesalamine (5-aminosalicylic acid) is the active component of sulfasalazine, but specific MOA is unknown; probably inhibits prostaglandin and leukotriene synthesis and release in colon. Action may be topical in terminal ileum and colon rather than systemic.