What Is Pentasa XR? Uses, Dosage, and What You Need to Know in 2026

Pentasa XR is a brand name for mesalamine extended-release capsules, a prescription medication used to treat ulcerative colitis (UC). It belongs to a drug class called aminosalicylates (also known as 5-ASA agents) and has been FDA-approved since 1987. Here's everything you need to know about what it is, what it treats, how to take it, and what makes it different from other similar medications.

What Is Pentasa XR?

Pentasa XR is an extended-release oral capsule containing mesalamine (also called 5-aminosalicylic acid, or 5-ASA). Each capsule contains thousands of tiny ethylcellulose-coated microspheres filled with mesalamine. These microspheres don't dissolve all at once — they gradually release mesalamine throughout the gastrointestinal tract as the capsule travels from the stomach through the small intestine to the colon.

The manufacturer, Takeda Pharmaceuticals, produces two capsule strengths: 250 mg and 500 mg. The drug is also available as generic mesalamine extended-release capsules, produced by Sun Pharmaceutical Industries and other manufacturers.

What Is Pentasa XR Used For?

FDA-approved indication:

• Induction of remission in mildly to moderately active ulcerative colitis in adults
• Treatment of mildly to moderately active ulcerative colitis in adults

Off-label uses (not FDA-approved but used in clinical practice):

• Crohn's disease — particularly following surgical resection to reduce risk of relapse
• Maintenance of UC remission (supporting evidence, though not the primary approved label)

What Is the Standard Dosage of Pentasa XR?

The recommended dose for treating active UC is:

• 1 gram (g) taken orally four times daily — for a total daily dose of 4 grams
• 250 mg capsules: Four capsules per dose (16 capsules per day)
• 500 mg capsules: Two capsules per dose (8 capsules per day)

Note: Safety and efficacy have not been established in pediatric patients. Always follow your prescriber's dosage instructions.

How to Take Pentasa XR

Key instructions for taking Pentasa XR:

• Swallow capsules whole with plenty of water — do not crush or chew the capsules or the contents inside
• If you have trouble swallowing, you may open the capsule and sprinkle the contents onto applesauce or yogurt — swallow immediately without chewing
• Can be taken with or without food
• Take at the same times each day to maintain consistent drug levels
• Stay well hydrated — drink plenty of fluids throughout the day
• Do not change brands without consulting your doctor — different mesalamine formulations are not interchangeable by dose

What Makes Pentasa XR Different from Other Mesalamine Products?

The key difference is where and how Pentasa XR releases mesalamine. While most mesalamine formulations (Lialda, Apriso, Delzicol) use pH-dependent coatings that target primarily the colon, Pentasa XR's ethylcellulose microsphere technology begins releasing mesalamine in the duodenum and continues releasing it throughout the jejunum, ileum, and colon.

This makes Pentasa XR unique for patients whose disease affects the small intestine, not just the colon. For most patients with colon-only UC, other once-daily mesalamine products may be clinically equivalent and more convenient.

Key Safety Information

Before taking Pentasa XR, tell your doctor if you have:

• Known allergy to salicylates, aspirin, or aminosalicylates
• Kidney or liver disease
• Phenylketonuria (PKU) — product contains phenylalanine
• Pregnancy or breastfeeding (use with caution; discuss with your doctor)

For a complete overview of side effects, see: Pentasa XR side effects. If you're having trouble finding Pentasa XR in stock, medfinder.com can help you locate it near you.