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Elmiron Side Effects

Generic Name: pentosan polysulfate sodium

Note: This page contains information about the side effects of pentosan polysulfate sodium. Some of the dosage forms included on this document may not apply to the brand name Elmiron.

For the Consumer

Applies to pentosan polysulfate sodium: oral capsule

In addition to its needed effects, some unwanted effects may be caused by pentosan polysulfate sodium (the active ingredient contained in Elmiron). In the event that any of these side effects do occur, they may require medical attention.

Severity: Moderate

If any of the following side effects occur while taking pentosan polysulfate sodium, check with your doctor or nurse as soon as possible:

  • Chills
  • difficulty in breathing
  • fever
  • skin rash or hives
  • sore throat
  • unusual bleeding or bruising
  • unusual tiredness or weakness
  • vision impairment

Minor Side Effects

Some of the side effects that can occur with pentosan polysulfate sodium may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

Less common or rare:
  • Abdominal pain
  • bleeding gums
  • constipation
  • diarrhea
  • difficulty or pain upon swallowing
  • dizziness
  • dryness of throat
  • hair loss
  • headache
  • heartburn
  • increased sensitivity of skin to sunlight
  • irritated or red eyes
  • itching
  • loss of appetite
  • nausea
  • nosebleed
  • ringing in the ears
  • runny nose
  • sores in mouth
  • stomach gas
  • stomach upset
  • vomiting

For Healthcare Professionals

Applies to pentosan polysulfate sodium: oral capsule


Gastrointestinal side effects have been reported the most frequently. These have included nausea, diarrhea, dyspepsia, vomiting, and rectal hemorrhage.[Ref]

In a phase 4 study of patients with interstitial cystitis (n=380) taking pentosan polysulfate sodium, the incidence of rectal hemorrhage was reported at 15% in patients taking doses of 900 mg/day versus 6.3% in patients taking the recommended daily dosage of 300 mg/day.[Ref]


Dermatologic side effects have included alopecia, pruritus, and urticaria.[Ref]

Nervous system

Nervous system side effects have included headache (3%) and dizziness (1%). Hyperkinesia, insomnia, and depression have also been reported.[Ref]


Hematologic side effects have included anemia, ecchymosis, increased prothrombin time, increased partial thromboplastin time, and thrombocytopenia.[Ref]

There have been case reports of thrombocytopenia similar to heparin induced thrombocytopenia associated with a parenteral form of pentosan polysulfate sodium. It should be used with caution in patients with a history of heparin induced thrombocytopenia.[Ref]


Hepatic side effects have included liver function abnormalities: mildly elevated (<2.5 normal) transaminase, alkaline phosphatase, gamma-glutamyl transpeptidase, and lactic dehydrogenase.[Ref]


Respiratory side effects have included pharyngitis, rhinitis, epistaxis, and dyspnea.[Ref]


Ocular side effects have included conjunctivitis, optic neuritis, amblyopia, and retinal hemorrhage.[Ref]


Hypersensitivity side effects have included allergic reactions and photosensitivity.[Ref]


1. "Product Information. Elmiron (pentosan polysulfate sodium)." Baker Norton Pharmaceuticals, Miami, FL.

2. Wedren H "Effects of sodium pentosanpolysulphate on symptoms related to chronic non-bacterial prostatitis. A double-blind randomized study." Scand J Urol Nephrol 21 (1987): 81-8

3. Sie P, Albarede JL, Robert M, Bouloux C, Lansen J, Chigot C, Correll S, Thouvenot JP, Boneu B "Tolerance and biological activity of pentosan polysulfate after intramuscular or subcutaneous administration for ten days in human volunteers." Thromb Haemost 55 (1986): 86-9

4. Mulholland SG, Hanno P, Parsons CL, Sant GR, Staskin DR "Pentosan polysulfate sodium for therapy of interstitial cystitis. A double-blind placebo-controlled clinical study." Urology 35 (1990): 552-8

5. Tardy-Poncet B, Tardy B, Grelac F, Reynaud J, Mismetti P, Bertrand JC, Guyotat D "Pentosan polysulfate-induced thrombocytopenia and thrombosis." Am J Hematol 45 (1994): 252-7

6. Goad KE, Horne MK 3rd, Gralnick HR "Pentosan-induced thrombocytopenia: support for an immune complex mechanism." Br J Haematol 88 (1994): 803-8

Not all side effects for Elmiron may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.