SANTA ROSA, Calif. – September 1, 2026. Patient advocates are calling on the U.S. Food and Drug Administration to formally reevaluate Elmiron® (pentosan polysulfate sodium, or PPS), or at minimum adopt stronger prescribing and monitoring requirements, citing a growing body of research linking long-term use of the drug to serious retinal and bowel complications. According to patients and researchers, these complications include effects that have not resolved over time and, in some cases, have required major bowel surgery.

PPS, sold as Elmiron®, has been the only FDA-approved oral medication for interstitial cystitis/bladder pain syndrome (IC/BPS) since 1996. A growing body of research has linked its use to a distinctive form of pigmentary maculopathy, prompting an FDA label update in 2020. New findings from the UCLA Stein Eye Institute raises the question of whether current warnings go far enough.

A Two-Organ Toxicity Profile

The UCLA Stein Eye Institute research team, tracking a small cohort of long-term PPS patients over a six-year period, documented findings in both the retina and the colon:

  • Eye damage that keeps progressing. Researchers observed a clear increase in retinal atrophy over the course of the study — more than double the number of affected eyes by the study’s end compared with the start — even though most patients had already stopped taking the drug.
  • Severe, silent bowel damage. Of the eight patients studied, six (75%) were found to have severe colonic polyposis — uncontrolled polyp growth in the bowel — on routine colonoscopy. Most had no gastrointestinal symptoms and no indication anything was wrong until they were screened. Patients in the study had taken PPS for a median of more than two decades.

Earlier, separate research has similarly linked long-term PPS use to inflammatory bowel disease and colonic dysplasia, with some patients requiring partial or total colectomy.

Why Some Physicians Still Prescribe It

Despite this evidence, PPS/Elmiron® is still prescribed. “Patients have reported that they were given new prescriptions of this medication with no warning from their doctor that it could affect their eyes or bowel,” said Jill Heidi Osborne, MA, founder of the Interstitial Cystitis Network. Some doctors have said the medication is safe because none of their patients have reported problems.

“This reasoning overlooks how PPS toxicity actually unfolds: retinal and bowel damage may develop silently over years, and can be misdiagnosed as age-related macular degeneration or unrelated GI conditions,” Osborne said. “The absence of a dramatic outcome in one physician’s practice is not evidence of safety — it may simply reflect how easily this toxicity is missed.”

Patients are calling for:

  • FDA reevaluation of Elmiron’s approval status, including consideration of an expanded black box warning that reflects the drug’s bowel toxicity in addition to its known retinal risks
  • Mandatory baseline and periodic retinal screening for any patient on long-term PPS therapy, with imaging sensitive enough to detect early pigmentary changes
  • Routine colonoscopy screening for patients with PPS exposure, given how often bowel damage was found in patients with no symptoms at all
  • Clear informed-consent conversations before starting or continuing PPS, so patients understand that both eye and bowel damage can be irreversible and may progress even after stopping the drug

Take Action

For the 2026 IC Awareness Month campaign, patients who have experienced retinal and/or bowel complications while using this medication are urged to report their symptoms to the FDA’s MedWatch database: https://www.fda.gov/safety/medwatch-fda-safety-information-and-adverse-event-reporting-program

Patients are also encouraged to share their experience with their Congressperson and Senators and to request a formal FDA review of the drug’s safety and effectiveness.

About the Interstitial Cystitis Network

The Interstitial Cystitis Network (ICN) has provided patient education and support for those struggling with interstitial cystitis/bladder pain syndrome (IC/BPS), chronic pelvic pain, and related urologic conditions for more than 30 years. Founded and led by Jill Heidi Osborne, MA, the ICN offers research-based education, advocacy, and support to patients nationwide.

Media Contact: 

Jill Heidi Osborne MA, Founder
Interstitial Cystitis Network – icnetwork.org
800-928-7496
707-538-9442
icnetwork@mac.com

Suggested Reading & Related Studies

  1. Feo A, et al. Spectrum of Colopathy and Severe Polyposis Associated With Pentosan Polysulfate Sodium Maculopathy: A Retrospective Case Series. Am J Ophthalmol. 2026 Jul;287:1-13.
  2. Anderson J, et al. Pentosan polysulfate–associated dysplasia in patients with inflammatory bowel disease: a case series. Am J Gastroenterol 2023;118(5):905–908.
  3. Jung EH, et al. Colopathy associated with pentosan polysulfate use. Front Pharmacol. 2025;16:1494467.
  4. Santina A, Feo A, Bousquet E, et al. Pentosan polysulfate sodium maculopathy: final analysis of a prospective cohort, updated review, and association with inflammatory bowel disease. Surv Ophthalmol. 2025;70(3):583–592.
  5. Osborne J. The Tragic and Tarnished History of Elmiron. IC Network. Updated July 26, 2026. 
  6. Lenzer J, Brownlee S. FDA Approved And Ineffective. The Lever. June 5, 2025


Note: This release is intended for general informational purposes and is not a substitute for professional medical advice. Patients currently taking Elmiron/pentosan polysulfate sodium should not stop or change their medication without first consulting their prescribing physician.