Introduction

Semisynthetic low molecular weight heparinoid; a uroprotective agent resembling glycosaminoglycans.

Uses for Pentosan

Interstitial Cystitis

Symptomatic relief of bladder pain or discomfort associated with interstitial cystitis; designated an orphan drug by FDA for this use.

Pentosan Dosage and Administration

Administration

Oral Administration

Administer with water ≥1 hour before or 2 hours after meals.

Dosage

Available as pentosan polysulfate sodium; dosage expressed in terms of the salt.

Adults

Interstitial Cystitis

Oral

100 mg 3 times daily for 3 months. If after 3 months no improvement and no dose-limiting adverse effects occur, may continue therapy for another 3 months.

Manufacturer states that if no improvement of pain is observed by 6 months, the clinical benefits and risks of continued therapy are unknown. However, data from a long-term clinical study indicate overall continued symptomatic improvement (e.g., pain, urgency, urinary frequency, nocturia) during 1–2 years of therapy.

Some clinicians recommend a dosage of 200 mg twice daily^{† [off-label]}; this dosage appears to be effective and promotes greater patient compliance.

Special Populations

Hepatic Impairment

No specific dosage recommendations. (See Hepatic Impairment under Cautions.)

Renal Impairment

No specific dosage recommendations.

Geriatric Patients

No specific dosage recommendations.

Contraindications

• Known hypersensitivity to pentosan polysulfate, structurally related compounds, or any ingredient in formulation.

Warnings/Precautions

Hematologic Effects

Pentosan polysulfate is weak anticoagulant.

Rectal hemorrhage and bleeding complications of ecchymosis, epistaxis, and gum hemorrhage reported.

Evaluate patients at increased risk for hemorrhage including those undergoing invasive procedures, with signs and symptoms of coagulopathy, or receiving concomitant drugs that affect hemostasis. (See Specific Drugs under Interactions.)

Delayed immunoallergic thrombocytopenia similar to heparin-induced thrombocytopenia with symptoms of thrombosis and hemorrhage reported with sub-Q, IM, or sublingual administration of a different formulation of pentosan polysulfate.

Use with caution in patients with history of heparin-induced thrombocytopenia. Carefully evaluate patients with thrombocytopenia prior to initiation of therapy.

Thrombocytopenia and elevations in PT and partial thromboplastin time (PTT) reported in patients with elevated liver function test results. Such effects not observed in healthy men receiving ≤1.2 g of pentosan polysulfate sodium daily (a dosage greater than the recommended 100 mg 3 times daily) for 8 days.

Concomitant Illnesses

Carefully evaluate patients with diseases such as aneurysms, hemophilia, GI ulcerations, polyps, or diverticula prior to initiation of therapy.

Hepatic Effects

Mild and usually transient elevations (<2.5 times ULN) of serum aminotransferases, alkaline phosphatase, γ-glutamyl transpeptidase, and LDH concentrations reported in about 1.2% of patients. Such abnormalities usually occur 3–12 months after initiation of therapy and generally not associated with jaundice or other clinical signs and symptoms. These elevations may remain unchanged or rarely progress with continued use.

Alopecia

Alopecia, primarily alopecia areata (limited to single area on scalp), reported; may occur within first 4 weeks of initiation of therapy.

Specific Populations

Pregnancy

Category B.

Lactation

Not known whether pentosan polysulfate is distributed into milk. Use with caution in nursing women.

Pediatric Use

Safety and efficacy in pediatric patients <16 years of age not established.

Hepatic Impairment

Use with caution. Not evaluated in patients with hepatic impairment. (See Hepatic Effects under Cautions.)

Hepatic impairment might alter pharmacokinetics; pentosan polysulfate is metabolized in the liver. (See Metabolism under Pharmacokinetics.)

Common Adverse Effects

Rectal hemorrhage, alopecia, diarrhea, nausea, headache, blood in stool, rash, dyspepsia, abdominal pain, abnormal liver function tests, dizziness, bruising.

Administration

Oral Administration

Administer with water ≥1 hour before or 2 hours after meals.

Dosage

Available as pentosan polysulfate sodium; dosage expressed in terms of the salt.

Adults

Interstitial Cystitis

Oral

100 mg 3 times daily for 3 months. If after 3 months no improvement and no dose-limiting adverse effects occur, may continue therapy for another 3 months.

Manufacturer states that if no improvement of pain is observed by 6 months, the clinical benefits and risks of continued therapy are unknown. However, data from a long-term clinical study indicate overall continued symptomatic improvement (e.g., pain, urgency, urinary frequency, nocturia) during 1–2 years of therapy.

Some clinicians recommend a dosage of 200 mg twice daily^{† [off-label]}; this dosage appears to be effective and promotes greater patient compliance.

Special Populations

Hepatic Impairment

No specific dosage recommendations. (See Hepatic Impairment under Cautions.)

Renal Impairment

No specific dosage recommendations.

Geriatric Patients

No specific dosage recommendations.

Drugs that Affect Hemostasis

Potential increased risk of hemorrhage with concurrent use of drugs that affect hemostasis.

Monitor for hemorrhage during concurrent administration.

Specific Drugs