Pentosan polysulfate

Pentosan polysulfate (sold under the name Elmiron by Ortho-McNeil Pharmaceutical, inc.) is the only oral medication approved by the U.S. FDA for the treatment of interstitial cystitis, also known as painful bladder syndrome.

Interstitial cystitis/painful bladder syndrome
Interstitial cystitis/painful bladder syndrome (IC/PBS) patients struggle with symptoms of urinary frequency, urgency, pressure and/or pain, as well as nocturia (frequent urination at night), dyspareunia (painful intercourse), pain and/or discomfort while sitting in a car, while driving and/or travelling.

The origin/cause of IC/PBS is unknown though a number of theories are currently under consideration. Urine cultures are typically negative for infection, yet it is not unusual for patients to believe that they have had infections for years rather than IC/PBS, because the symptoms of an infection are nearly identical to the symptoms of IC/PBS.

Pentosan polysulfate is available as pills or directly infused into the bladder.

Transmissible spongiform encephalopathies
Recently pentosan polysulfate has gained attention as possibly being effective in the treatment of Creutzfeldt-Jakob disease (CJD), although there is as yet no definitive evidence for this other than results of the ongoing treatment (published) of one patient in Northern Ireland and around six other patients in mainland Britain.

Around 15 other patients in non-UK countries have also received this treatment in an attempt to halt or slow down CJD and related disease progression.

Osteoarthrosis in adult dogs
Recently PPN is being marketed as an alternative for the treatment of lameness and pain of degenerative joint disease/osteoarthrosis (non-infectious arthrosis) in the skeletally mature dog.

Cartrophen-Vet is a 100mg/ml formulation of Pentosan polysulphate that has been used in Australia since the early 1990s. It is produced by Biopharm Australia.

3 mg/kg PPN is given subcutaneously every 5-7 days for 4 treatments. Subsequent single booster shots are usually given every 3-6 months.

Pharmacology
Pentosan is believed to work by providing a protective coating to the damaged bladder wall. The critical flaw of the medication, however, is its exceptionally poor bioavailability when taken orally. Research presented late in 2005 by Alza Pharmaceuticals demonstrates that more than 94% of the medication is excreted, intact, in feces without providing any beneficial effect. Their research found that only 6% was excreted through urine. The drug must be taken for several months for most patients to achieve some benefit.

More recently, however, pentosan polysulfate has been studied as part of a "rescue instillation" which is placed directly in the bladder and can, perhaps, provide better effectiveness. C. Lowell Parsons has presented a research study which shows a 90% effectiveness in reducing the symptoms of IC/PBS patients by using this instillation.

Side effects
Patients who have taken pentosan orally report a variety of side effects, primarily GI complaints such as diarrhea, heartburn, stomach pain. Hair loss, headache, rash, insomnia have also been reported. One concern is the potential for increased blood coagulation times with this medication. Some patients have reported that they bruise more easily. In some cases, patients are asked to stop medication before any major surgical procedures to reduce the likelihood of bleeding.