FDA-filed SPL labeling · retrieved through openFDA

Olsalazine

Olsalazine is an aminosalicylate medication used to maintain remission of ulcerative colitis in adults who cannot tolerate sulfasalazine.

Brand name Dipentum
Drug classes Aminosalicylate
Rx Form 1 Route Oral
Dr. Brian Staiger, PharmD, BCPS
Reviewed by Last reviewed Jul 10, 2026
🧬 Where this information comes from Click to expand

The clinical label records used on this page are FDA-filed Structured Product Labeling (SPL) retrieved through openFDA. We identified 1 clinical label set within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. Forms, routes, brands, labelers, strengths, and NDC product-record counts are built separately from matching FDA National Drug Code Directory records. The linked DailyMed document is a representative official source for verification, not the page’s only clinical source. View the linked label on DailyMed →

At a glance
Linked label effectiveMay 15, 2026
AvailabilityRx
Earliest approval/marketing year 1990
FDA-listed product records 5
Boxed warningNone found in compared labels
How we combine label and product data →
No current FDA shortage listed · checked Sep 18, 2026
Olsalazine at a glance The quick version — the full detail is in the Patient Information Guide below.
💊
HelloPharmacist Editorial Team Bottom Line
Dipentum (olsalazine) is a targeted anti-inflammatory taken by mouth twice daily to help keep ulcerative colitis in remission, specifically in people who can't tolerate sulfasalazine. The most important things to watch are your kidney function, any signs of worsening symptoms that might be a drug reaction rather than a flare, and staying well-hydrated. Take it exactly as prescribed, keep your follow-up appointments, and let your doctor know about all other medications you're taking.

📖 Olsalazine: Patient Information Guide

A plain-language walkthrough of Olsalazine — what it treats, how it works, how it’s taken, side effects, warnings and interactions. Tap any section to expand it.

🎯What it's used for

Olsalazine is an aminosalicylate used to treat ulcerative colitis. Its only currently supported use is through Dipentum capsules:

  • Dipentum (oral capsule) is approved to maintain remission of ulcerative colitis in adult patients who cannot tolerate sulfasalazine.
⚙️How it works

When you take olsalazine by mouth, nearly all of it reaches the colon without being absorbed in the upper digestive tract. Once there, bacteria in the colon rapidly break it down into two molecules of mesalamine (5-aminosalicylic acid), the active compound. Mesalamine works directly on the inner lining of the colon to reduce inflammation — likely by blocking enzymes (cyclooxygenase) that produce inflammatory chemicals called prostaglandins, as well as other inflammatory pathways. This localized action means very high concentrations of the drug reach the colon while relatively little is absorbed into the bloodstream.

💊How it's taken

Dipentum capsules are taken by mouth twice daily. Before starting, your doctor will check your kidney function, and will continue to monitor it periodically during treatment. Drink plenty of fluids every day while on Dipentum to help protect your kidneys and reduce the risk of kidney stones. Always follow your prescriber's instructions for your specific dose and schedule.

🤒Side effects — in detail

The most commonly reported side effects with Dipentum include:

  • Diarrhea or loose stools (the most frequent reason people stop the medication)
  • Abdominal pain or cramping
  • Nausea
  • Joint pain
  • Skin rash or itching
  • Upper respiratory infection
  • Depressed mood
  • Vomiting

More serious reactions — including kidney problems, severe skin reactions, heart or liver inflammation, and blood cell disorders — are less common but require immediate medical attention if they occur. Contact your doctor right away if you develop worsening abdominal symptoms, bloody diarrhea, chest pain, shortness of breath, yellowing of the skin or eyes, or unusual bruising or bleeding.

⚠️Warnings & precautions
  • Kidney damage: Mesalamine (what olsalazine converts to) can cause kidney inflammation or failure. Kidney function must be checked before starting and monitored regularly. Stop the medication if kidney function worsens.
  • Acute intolerance syndrome: Some people develop a reaction that looks like a colitis flare but is actually caused by the drug — cramping, bloody diarrhea, fever, headache, and rash. If this is suspected, stop the medication and contact your doctor.
  • Hypersensitivity reactions: Serious allergic reactions can involve the heart (myocarditis, pericarditis), lungs, liver, kidneys, or blood. Stop Dipentum and seek care if these are suspected.
  • Liver failure: Rare but serious cases of liver failure have been reported, especially in people with pre-existing liver disease.
  • Severe skin reactions: Rare, life-threatening reactions such as Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) have been reported. Stop the drug immediately at the first sign of blistering or widespread skin breakdown.
  • Kidney stones (nephrolithiasis): Mesalamine-containing stones can form and are not detectable on standard X-rays or CT scans. Staying well-hydrated reduces this risk.
  • Sun sensitivity: Especially in people with pre-existing skin conditions like eczema. Use sunscreen and protective clothing outdoors.
🔀What it interacts with

Tell your doctor and pharmacist about all medications you take, because Dipentum has several important interactions:

  • NSAIDs (ibuprofen, naproxen, etc.): Taking these with Dipentum raises the risk of kidney damage — kidney function should be monitored closely.
  • Azathioprine or 6-mercaptopurine: Combining these with Dipentum increases the risk of serious blood cell problems, including bone marrow failure. Blood counts need to be monitored.
  • Low molecular weight heparins or heparinoids: Increased bleeding risk, particularly around the time of spinal or epidural anesthesia. Dipentum may need to be stopped beforehand.
  • Varicella (chickenpox) vaccine: Avoid Dipentum for 6 weeks after receiving this vaccine to reduce the risk of Reye's syndrome, a rare but serious condition.
  • Other kidney-toxic drugs: Any medication known to affect the kidneys can compound the risk when used alongside Dipentum.

This is not a complete list of interactions. Always talk with your doctor or pharmacist before starting, stopping, or changing any medication.

📋Before taking it
  • Allergy to salicylates or aminosalicylates: Do not take Dipentum if you are allergic to aspirin, sulfasalazine, mesalamine, or any ingredient in the capsule.
  • Previous reaction to sulfasalazine: You may have a similar reaction to olsalazine — discuss this with your doctor.
  • Kidney disease: Kidney function must be assessed before starting. Use with caution and close monitoring if you have impaired kidneys.
  • Liver disease: People with pre-existing liver problems are at higher risk for liver failure; weigh the risks and benefits with your doctor.
  • Pregnancy: Published human data have not clearly linked mesalamine to birth defects, but animal studies showed harm at high doses. Discuss with your doctor — uncontrolled ulcerative colitis in pregnancy also carries risks.
  • Breastfeeding: Small amounts of mesalamine pass into breast milk. Watch your baby for diarrhea and discuss the decision to breastfeed with your doctor.
  • Children: Safety and effectiveness have not been established in pediatric patients.
  • Older adults (65+): Higher risk of blood cell disorders (such as low white blood cell or platelet counts). Blood counts should be monitored during treatment.
🚑If you take too much

Taking too much olsalazine can cause salicylate-type toxicity — symptoms include nausea, vomiting, abdominal pain, ringing in the ears, rapid breathing, dizziness, confusion, and in severe cases, seizures or electrolyte imbalances. There is no specific antidote. If an overdose is suspected, seek emergency medical care immediately; treatment focuses on supportive care, preventing further absorption, and maintaining fluid and electrolyte balance.

📡Pharmacodynamics — effects in the body

Olsalazine works by delivering high concentrations of mesalamine (5-aminosalicylic acid) directly to the lining of the colon, where it exerts a local anti-inflammatory effect. It appears to work by blocking enzymes involved in producing inflammatory chemicals such as prostaglandins and leukotrienes, which are elevated in people with ulcerative colitis. The precise relationship between mesalamine blood levels and its effectiveness or safety has not been fully characterized.

🔬Pharmacokinetics — how your body processes it

After you take olsalazine by mouth, 98–99% of it reaches the colon, where bacteria rapidly convert each molecule into two molecules of mesalamine — only about 2.4% is absorbed before it gets there. The drug has a very short half-life of roughly 0.9 hours in the bloodstream. Mesalamine is released slowly in the colon, creating high local concentrations, and is then partially absorbed and metabolized — mainly in the colon lining and liver — before being excreted in the urine and feces. Less than 1% of olsalazine itself is recovered in the urine.

📦How to store it

Store at 20°C to 25°C (68°F to 77°F).

📄 Written from Olsalazine’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Every point is grounded in that labeling — nothing is invented. How we use AI →

17

Supplements & herbs that interact with Olsalazine

17 supplements and herbal products have documented interactions with Olsalazine in the licensed clinical database we use. Most are manageable — but your pharmacist should know about everything you take, including vitamins and herbals.

Severity mix
  • Major · 1
  • Moderate · 7
  • Minor · 9
Every supplement checked against Olsalazine — ranked by severity The full interaction hub: 1 major · 7 moderate · 9 minor · every one linked to its full report. Check Olsalazine against your exact supplements

Educational information from a licensed clinical database (Natural Medicines) — see our data sources & update cadence. Not medical advice: an interaction being documented does not mean it will happen to you; do not start or stop medications or supplements without professional guidance.

🩺 Pharmacist Counseling Corner

Quick, plain-English answers to the questions patients ask most about Olsalazine — the kind of thing our pharmacy team would talk through with you at the counter.

What exactly is Dipentum for, and why was I prescribed it instead of another medication?
Dipentum is used to keep ulcerative colitis in remission — meaning it helps prevent your symptoms from coming back after they've been controlled. It's prescribed specifically for people who can't tolerate sulfasalazine, a more commonly used medication for ulcerative colitis. If sulfasalazine caused you side effects or an allergic reaction, Dipentum may be a better fit for you.
How should I take these capsules — do I need to take them with food?
Dipentum capsules are taken twice daily by mouth. The label doesn't specify taking them with food, so follow whatever instructions your prescriber gave you. One thing that is important: drink plenty of fluids throughout the day while you're on this medication — it helps protect your kidneys and reduces the chance of developing kidney stones.
What side effects should I expect, and which ones should make me call my doctor?
The most common side effects are diarrhea or loose stools, stomach cramps, nausea, and joint pain — diarrhea is actually the main reason some people stop the medication. You should call your doctor right away if you develop worsening cramping or bloody diarrhea (which could be a drug reaction rather than a flare), chest pain, shortness of breath, yellowing of the skin or eyes, severe skin blistering, or unusual bruising. These could be signs of something more serious that needs attention quickly.
Why does my doctor want to check my kidneys before I start this medication?
That's a really important precaution. The active compound that olsalazine converts into — called mesalamine — is processed mainly by the kidneys, and in some people it can cause kidney inflammation or reduce kidney function over time. Checking your kidneys at the start gives your doctor a baseline, so they can catch any changes early. Your kidneys will be monitored periodically while you're on the medication too.
Are there any medications I should avoid while taking Dipentum?
Yes, a few important ones. Common pain relievers like ibuprofen and naproxen (NSAIDs) can increase the risk of kidney problems when combined with Dipentum, so try to avoid them or use them only with your doctor's guidance. If you take azathioprine or 6-mercaptopurine for your colitis, your doctor will need to monitor your blood counts more closely. Also, if you're getting the chickenpox vaccine, avoid Dipentum for six weeks afterward. Always tell any doctor or pharmacist you see that you're on this medication.
Is it safe to take Dipentum if I'm pregnant or breastfeeding?
This is something to talk through carefully with your doctor. Human studies so far haven't clearly linked olsalazine to birth defects, but animal studies showed some harmful effects at high doses — so the risks and benefits need to be weighed for your situation. If you're breastfeeding, small amounts of the active compound do pass into breast milk, and there are a few reports of diarrhea in breastfed babies. Your doctor can help you decide what's best, taking into account that untreated ulcerative colitis during pregnancy also carries its own risks.
Is Olsalazine available over the counter?
Olsalazine is dispensed by prescription according to its FDA labeling, so it isn't sold over the counter. Your prescriber and pharmacist will determine if it's appropriate for you.
When was Olsalazine first available?
Olsalazine has been available in the United States since at least 1990, based on FDA approval history (Drugs@FDA) and product marketing records.
Who makes Olsalazine?
Olsalazine is supplied by 3 manufacturers listed in the FDA NDC Directory, including Meda Pharmaceuticals Inc., Viatris Specialty LLC, Matrix Pharmacorp Private Limited.

💬 Answers drafted from Olsalazine’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Grounded in that labeling — nothing is made up. How we use AI →

🧰 Keep exploring

💊 How Olsalazine comes

Olsalazine is available in 1 form. Different forms and brands can have different approved uses, doses, schedules, and directions. Follow the instructions for your exact product, and do not switch forms without guidance from your prescriber or pharmacist.

Capsule

By mouth
Brands Dipentum
How this form is used
What it may be used for
  • Dipentum capsules are used to maintain remission of ulcerative colitis in adults who are intolerant of sulfasalazine
Important instructions
  • Dipentum capsules are taken by mouth twice daily
  • Drink adequate fluids throughout the day while taking Dipentum
  • Dipentum requires a kidney function check before starting and periodically during treatment
  • Follow your prescriber's instructions for the exact dose and schedule of Dipentum
Available strengths 1 strength
4 FDA-listed product records

📊 Olsalazine across the U.S. market

How Olsalazine appears in the FDA’s National Drug Code Directory — including its dosage forms, strengths, brand names, manufacturers, and FDA-listed product records. These are directory records, not sales or prescription volume.

1
Dose forms
3
Manufacturers
1
Brand names
5
FDA-listed product records
1990
First marketed

Also listed with the FDA, not a patient dose form: Powder (1) — bulk drug substance sold to compounders/manufacturers and multi-item kits. These aren’t counted in the dose-form total above.

Meda Pharmaceuticals Inc.40%
Viatris Specialty LLC40%
Matrix Pharmacorp Private Limited20%

Share of FDA-listed product records by manufacturer — FDA National Drug Code Directory. Record counts are not sales or prescription volume.

🔍 Compare Olsalazine products

A representative set of FDA-listed product records for Olsalazine — across manufacturers, strengths, and dosage forms, grouped by form with each product’s manufacturer and how the FDA approved it. The same medicine may be made and packaged by different companies, so a single drug can have many directory entries. (It’s also why a refill can look different — a new shape, color, or box — even though it contains the same medication.)

Strength Route Manufacturer / Labeler Category Details
💊Capsule
250 mg Oral Meda Pharmaceuticals Inc. × 2 listings NDA View NDC →
250 mg Oral Viatris Specialty LLC × 2 listings NDA View NDC →
💊Bulk drug substance
1 kg/kg Matrix Pharmacorp Private Limited BULK INGREDIENT View NDC →

Showing 5 of 5 products — FDA National Drug Code Directory. See every product, package size and price: browse all 5 Olsalazine NDCs →

RxNorm Concept Web — From Ingredient to Every Form and Strength

This page starts with one ingredient concept (IN). The branches below show its dose-form concepts (SCDF), then the available clinical drug and strength concepts (SCD). Combination products remain separate concepts with their own pages.

Ingredient (IN) Olsalazine RxCUI 32385 2 dose forms · 2 strengths
  1. Dose form (SCDF) Oral Capsule RxCUI 373143 In current FDA listings
    Clinical drug / strength (SCD) sodium 250 MG RxCUI 905162
  2. Dose form (SCDF) Oral Tablet RxCUI 373144 No current FDA listing
    Clinical drug / strength (SCD) sodium 500 MG RxCUI 905166

Look up RxCUI 32385 in the RxCUI Atlas →

RxNorm is the U.S. National Library of Medicine’s normalized drug vocabulary. Its concept hierarchy can include forms that are not currently marketed; the status on each branch compares that concept with current FDA listings. RxCUIs identify vocabulary concepts, not individual packages or manufacturers.

🏷️ Sold under these brand names

Dipentum

🏭 Manufacturers & labelers

Meda Pharmaceuticals Inc. 2 Viatris Specialty LLC 2 Matrix Pharmacorp Private Limited 1

RxNorm drug class

Olsalazine belongs to the Aminosalicylate class.

Pharmacologic class Aminosalicylate
Drug family (ATC) Aminosalicylic acid and similar agents

Classified by RxNorm RxClass — the U.S. National Library of Medicine's standardized drug-classification service (Established Pharmacologic Class from the FDA, the ATC drug family from the WHO, and mechanism of action). Reference only, not medical advice.

🔬 Where this comes from

Core label, product, RxNorm, safety, and utilization data on this page come from the sources identified below. AI-written, editorial, and licensed sections are labeled separately.

📄
FDA-filed drug labels (SPL) Uses, dosing, warnings & side effects from SPL records retrieved through openFDA; the linked representative set can be verified on DailyMed. ✓ Linked label effective May 15, 2026
🏭
Forms, brands & labelersAggregated from ingredient-matched FDA National Drug Code Directory product records for Olsalazine.
📈
Real-world reportsThe FDA Adverse Event Reporting System (FAERS), served through openFDA.
🚨
Recalls & shortagesopenFDA drug-enforcement reports and the FDA drug-shortage database.
🧾 Clinical label set — FDA-filed SPL labels retained for Olsalazine after exact ingredient or ingredient-combination matching and applicable route/form matching
Clinical labels in scope
1
NDC products indexed
5
Distinct labelers/manufacturers represented
3
Linked representative label
Meda Pharmaceuticals Inc.
Linked label effective
May 15, 2026
Composite sections available
21
Linked SPL Set ID
8512d0c6-db4e-4673-b3b4-28975c18413f
Linked SPL Document ID
6ef9e69e-bfc6-4136-a675-ac5519c98d30
Open the linked representative label on DailyMed ↗
NDC package records associated with this linked SPL 1

How we combine label and product data

HelloPharmacist combines public FDA and NLM records; we don’t author the underlying clinical facts. We identified 1 FDA-filed SPL label set within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. The representative label is the starting point for the displayed reference monograph; the 12 largest stored in-scope SPL records, which may include that representative, are compared section by section, and the longest available version of each section is retained. Forms, routes, brands, labelers, product-listed strengths, and product-record counts are aggregated separately from ingredient-matched FDA NDC Directory records; package records listed above are associated with the linked SPL; and the normalized concept hierarchy comes from NLM RxNorm.

For canonical ingredient pages, bounded product-attributed indication and administration excerpts may be added to the AI evidence, and the generator is instructed to preserve available product, brand, route, and form qualifiers instead of treating one label as universal. Where a section is identified as AI-written, its plain-language text is generated from bounded label evidence. New draft drug pages remain in the admin review queue before first publication. Meda Pharmaceuticals Inc. is the representative DailyMed label linked for verification and dates; it is not the sole source used for the page.

This is general education, not medical advice — always consult your doctor or pharmacist about your medications and any medical condition. For the exact wording of the linked representative label, view that label on DailyMed; some displayed composite sections may come from other in-scope SPL labels. Learn how we use AI and our data sources & update cadence.