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Medically reviewed by Last updated on Jul 17, 2020.


(ole SAL a zeen)

Index Terms

  • Olsalazine Sodium

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Capsule, Oral, as sodium:

Dipentum: 250 mg

Brand Names: U.S.

  • Dipentum

Pharmacologic Category

  • 5-Aminosalicylic Acid Derivative


Mesalamine (5-aminosalicylic acid) is the active component of olsalazine; the specific mechanism of action of mesalamine is unknown; however, it is thought that it modulates local chemical mediators of the inflammatory response, especially leukotrienes, and is also postulated to be a free radical scavenger or an inhibitor of tumor necrosis factor (TNF); action appears topical rather than systemic.


<3%; very little intact olsalazine is systemically absorbed


Primarily via colonic bacteria to active drug, 5-aminosalicylic acid (5-ASA)


Primarily feces; urine (<1%)

Time to Peak

~1 hour

Half-Life Elimination

54 minutes

Protein Binding

Plasma: >99%

Use: Labeled Indications

Ulcerative colitis, remission maintenance: Maintenance of remission of ulcerative colitis in adults intolerant to sulfasalazine.

Off Label Uses

Ulcerative colitis, remission induction

Data from 2 small randomized, double-blind, placebo-controlled studies and 1 small randomized study of olsalazine in the treatment of ulcerative colitis supports the use of olsalazine for induction of remission in patients with mild to moderate ulcerative colitis [Feurle 1989], [Kruis 1998], [Zinberg 1990].

Based on the American Gastroenterological Association (AGA) guidelines on the management of mild to moderate ulcerative colitis, olsalazine is an option for induction of remission in patients with mild to moderate ulcerative colitis [AGA [Ko 2019]].


Hypersensitivity to olsalazine, aminosalicylates, salicylates, or metabolites or any component of the formulation

Dosing: Adult

Ulcerative colitis, remission maintenance: Oral: 1 g/day in 2 divided doses.

Ulcerative colitis, remission induction (off-label use): Oral: 2 to 3 g/day in 2 to 4 divided doses (Feurle 1989; Kruis 1998; Zinberg 1990).

Dosing: Geriatric

Refer to adult dosing.


Oral: Administer with food in evenly divided doses. Maintain adequate hydration during therapy (to minimize nephrolithiasis risk).


Store at 20°C to 25°C (77°F); excursions permitted to 15°C to 30°C (59°F to 86°F).

Drug Interactions

Cardiac Glycosides: 5-Aminosalicylic Acid Derivatives may decrease the serum concentration of Cardiac Glycosides. Monitor therapy

Heparin: 5-Aminosalicylic Acid Derivatives may enhance the adverse/toxic effect of Heparin. Specifically, the risk for bleeding/bruising may be increased. Monitor therapy

Heparins (Low Molecular Weight): 5-Aminosalicylic Acid Derivatives may enhance the adverse/toxic effect of Heparins (Low Molecular Weight). Specifically, the risk for bleeding/bruising may be increased. Monitor therapy

Myelosuppressive Agents: 5-Aminosalicylic Acid Derivatives may enhance the myelosuppressive effect of Myelosuppressive Agents. Monitor therapy

Nonsteroidal Anti-Inflammatory Agents: May enhance the nephrotoxic effect of 5-Aminosalicylic Acid Derivatives. Monitor therapy

Thiopurine Analogs: 5-Aminosalicylic Acid Derivatives may enhance the myelosuppressive effect of Thiopurine Analogs. 5-Aminosalicylic Acid Derivatives may increase serum concentrations of the active metabolite(s) of Thiopurine Analogs. Specifically, exposure to the active 6-thioguanine nucleotides (6-TGN) may be increased. Monitor therapy

Varicella Virus-Containing Vaccines: 5-Aminosalicylic Acid Derivatives may enhance the adverse/toxic effect of Varicella Virus-Containing Vaccines. The primary concern is the potential development of Reye's Syndrome, a condition that has been associated with the use of salicylates in children with varicella infections. Management: Avoid administration of salicylates for at least 6 weeks after adminstration of a varicella virus-containing vaccine. Consider therapy modification

Test Interactions

May cause falsely elevated urinary normetanephrine levels when measured by liquid chromatography with electrochemical detection (due to similarity in the chromatograms of normetanephrine and mesalamine's main metabolite, N-acetylaminosalicylic acid).

Adverse Reactions

The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified.

>10%: Gastrointestinal: Diarrhea (11% to 17%)

1% to 10%:

Central nervous system: Depression (2%), dizziness (≤1%), vertigo (≤1%)

Dermatologic: Skin rash (2%), pruritus (1%)

Gastrointestinal: Abdominal cramps (≤10%), abdominal pain (≤10%), nausea (5%), bloating (2%), stomatitis (1%), vomiting (1%)

Neuromuscular & skeletal: Arthralgia (4%)

Respiratory: Upper respiratory tract infection (2%)

<1%, postmarketing, and/or case reports: Alopecia, anemia, angioedema, aplastic anemia, bloody stools, blurred vision, bronchospasm, cholestatic hepatitis, cholestatic jaundice, chest pain, chills, dehydration, dyspnea, dysuria, emotional lability, eosinophilia, epigastric distress, erythema, erythema nodosum, exacerbation of ulcerative colitis, fever, flatulence, hematuria, hemolytic anemia, hepatic cirrhosis, hepatitis, hepatic failure, hepatic necrosis, hot flash, hypermenorrhea, hypertension, impotence, increased gamma-glutamyl transferase, increased lactate dehydrogenase, increased serum alkaline phosphatase, increased serum ALT, increased serum AST, increased serum bilirubin, insomnia, interstitial nephritis, interstitial pneumonitis, irritability, jaundice, Kawasaki-like syndrome, leukopenia, local discomfort (rectal), lymphocytopenia, muscle cramps, myalgia, myocarditis, nephrotic syndrome, neutropenia, orthostatic hypotension, palpitations, pancreatitis, pancytopenia, paresthesia, pericarditis, peripheral edema, peripheral neuropathy, proteinuria, rectal hemorrhage, reticulocytosis, rigors, second degree atrioventricular block, skin photosensitivity, tachycardia, thrombocytopenia, tinnitus, tremor, urinary frequency, watery eyes, xerophthalmia, xerostomia


Concerns related to adverse effects:

• Diarrhea: Commonly occurs and may be dose related; must be distinguished from underlying symptoms of ulcerative colitis.

• Hypersensitivity reactions: Mesalamine-induced hypersensitivity reactions have been reported and may include internal organ involvement, such as hepatitis, myocarditis, pericarditis, nephritis, hematologic abnormalities, and/or pneumonitis. Monitor for signs and symptoms of hypersensitivity; discontinue treatment if hypersensitivity occurs.

• Intolerance syndrome: May cause an acute intolerance syndrome (cramping, acute abdominal pain, bloody diarrhea; sometimes fever, headache, rash); may be hard to discern from an exacerbation; monitor for worsening of symptoms and discontinue immediately if syndrome occurs or is suspected.

• Photosensitivity: Use with caution in patients with preexisting skin conditions (including atopic dermatitis and atopic eczema); severe photosensitivity reactions have been reported. Use skin protection (protective clothing and broad-spectrum sunscreen) and avoid prolonged exposure to sunlight and ultraviolet light.

• Renal effects: Renal impairment (including minimal change disease, acute and chronic interstitial nephritis, and renal failure) has been reported. A renal function evaluation is recommended prior to initiation of therapy and periodically during treatment. Evaluate risk versus benefit in patients with renal impairment, with a history of renal disease, or concurrently taking nephrotoxic medications. Cases of nephrolithiasis (including stones with 100% mesalamine content) have occurred with mesalamine use. Stones may be radiotransparent and undetectable by standard imaging. Ensure patients are adequately hydrated during therapy.

• Sulfasalazine hypersensitivity: Patients with hypersensitivity to sulfasalazine may react to mesalamine.

Disease-related concerns:

• Hepatic impairment: Evaluate risk versus benefit if therapy in patients with hepatic impairment; hepatic failure has been observed with other mesalamine (5-aminosalicylic acid) products.

• Renal impairment: Use with caution in patients with renal impairment, with a history of renal disease, or on nephrotoxic medications.

Special populations:

• Elderly: Use with caution in elderly patients; uncontrolled studies and postmarketing reports suggest an increased incidence of blood dyscrasias (ie, agranulocytosis, neutropenia, pancytopenia) in patients >65 years of age taking mesalamine-containing products.

Monitoring Parameters

Renal function (prior to and periodically during therapy); CBC (particularly in elderly patients); hepatic function; signs/symptoms of worsening acute intolerance syndrome or hypersensitivity reactions.

Pregnancy Considerations

Animal studies have demonstrated fetal developmental toxicities. There are no well-controlled studies in pregnant women. Use during pregnancy only if clearly necessary.

Patient Education

What is this drug used for?

• It is used to treat ulcerative colitis.

• It may be given to you for other reasons. Talk with the doctor.

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Abdominal pain

• Abdominal cramps

• Nausea

• Headache

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Kidney problems like unable to pass urine, blood in the urine, change in amount of urine passed, or weight gain

• Diarrhea

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.

Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.

Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a limited summary of general information about the medicine’s uses from the patient education leaflet and is not intended to be comprehensive. This limited summary does NOT include all information available about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not intended to provide medical advice, diagnosis or treatment and does not replace information you receive from the healthcare provider. For a more detailed summary of information about the risks and benefits of using this medicine, please speak with your healthcare provider and review the entire patient education leaflet.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.