General Information

Elmiron (pentosan polysulfate sodium) is a low molecular weight heparin-like compound with anticoagulant and fibrinolytic effects. 

Elmiron is specifically indicated for the relief of bladder pain or discomfort associated with interstitial cystitis.

Elmiron is supplied as a capsule for oral administration. The recommended dose is 300 mg/day taken as one 100 mg capsule orally three times daily. The capsules should be taken with water at least 1 hour before meals or 2 hours after meals. Patients receiving Elmiron should be reassessed after 3 months. If improvement has not occurred and if limiting adverse events are not present, Elmiron may be continued for another 3 months. The clinical value and risks of continued treatment in patients whose pain has not improved by 6 months is not known.

Mechanism of Action

Elmiron (pentosan polysulfate sodium) is a low molecular weight heparin-like compound with anticoagulant and fibrinolytic effects. The mechanism of action of pentosan polysulfate sodium in interstitial cystitis is not known.

Side Effects

Adverse effects associated with the use of Elmiron may include, but are not limited to, the following:

• Alopecia
• diarrhea
• nausea
• headache
• rash
• dyspepsia
• abdominal pain

Clinical Trial Results

FDA approval was based on two clinical trials for the relief of pain in patients with chronic interstitial cystitis (IC). 

One blinded, randomized, placebo-controlled study evaluated 151 patients (145 women, 5 men, 1 unknown) with a mean age of 44 years (range 18 to 81). Approximately equal numbers of patients received either placebo or Elmiron 100 mg three times a day for 3 months. Clinical improvement in bladder pain was based upon the patient’s own assessment. In this study, 28/74 (38%) of patients who received Elmiron and 13/74 (18%) of patients who received placebo showed greater than 50% improvement in bladder pain.

A second clinical trial, the physician’s usage study, was a prospectively designed retrospective analysis of 2,499 patients who received Elmiron 300 mg a day without blinding. Of the 2,499 patients, 2,220 were women, 254 were men, and 25 were of unknown sex. The patients had a mean age of 47 years and 23% were over 60 years of age. By 3 months, 1,307 (52%) of the patients had dropped out or were ineligible for analysis, overall, 1,192 (48%) received Elmiron for 3 months; 892 (36%) received Elmiron for 6 months; and 598 (24%) received Elmiron for one year. Patients had unblinded evaluations every 3 months for the patient’s rating of overall change in pain in comparison to baseline and for the difference calculated in “pain/discomfort” scores. At baseline, pain/discomfort scores for the original 2499 patients were severe or unbearable in 60%, moderate in 33% and mild or none in 7% of patients. At 3 months, 722/2499 (29%) of the patients originally in the study had pain scores that improved by one or two categories. By 6 months, in the 892 patients who continued taking Elmiron, an additional 116/2499 (5%) of patients had improved pain scores. After 6 months, the percent of patients who reported the first onset of pain relief was less than 1.5% of patients who originally entered in the study.