Elmiron (Pentosan Polysulfate Sodium) - Oral

What Is Elmiron?

Elmiron (pentosan polysulfate sodium) belongs to a family of anticoagulant drugs known as low molecular-weight heparins. Although other anticoagulants are used as blood thinners, Elmiron is indicated to treat discomfort or bladder pain related to interstitial cystitis (IC), a chronic condition that causes bladder pain and pressure.

Pentosan polysulfate sodium is thought to work by protecting the bladder. It creates a barrier on the bladder wall, which reduces leaks and prevents irritation and inflammation.

Elmiron is a prescription medicine available in capsules you take by mouth (oral).

Drug Facts

Generic Name: Pentosan polysulfate sodium

Brand Name(s): Elmiron

Drug Availability: Prescription

Administration Route: Oral

Therapeutic Classification: Urinary analgesic

Available Generically: No

Controlled Substance: N/A

Active Ingredient: Pentosan polysulfate sodium

Dosage Form(s): Capsule

What Is Elmiron Used For?

Elmiron is used to relieve bladder pain and discomfort associated with IC.

IC is a chronic bladder disorder that causes an inflamed or irritated bladder wall, leading to bladder scarring and stiffening. People with IC experience recurrent pain in the bladder or pelvic region and a frequent need to urinate. Clinical trials have shown that Elmiron can help in reducing these symptoms. However, it may not completely get rid of symptoms altogether.

How to Take Elmiron

Read the prescription label before you start taking Elmiron. Ask your healthcare provider or pharmacist to answer any questions you have about your medication.

Elmiron comes as a capsule you take by mouth. It is usually prescribed to be taken with water three times a day, one hour before or two hours after meals.

Do not change the dose or take Elmiron more often or longer than prescribed. Doing so will not cause your condition to improve any faster, and the risk of side effects will increase.

After three months of treatment, you and your healthcare provider will reassess whether you should continue taking Elmiron.


Store Elmiron at room temperature (between 68 F and 77 F). Keep the medication in the tightly closed container that it came in. Store it away from excess heat and moisture. Do not store your medication in the bathroom. Keep your medication locked up safely and out of reach of children and pets.

Do not keep unwanted or expired medications. Unneeded medications should be disposed of properly. Do not flush your medication down the toilet or drain. Instead, dispose of your medication through a medicine take-back program. You can find these programs at retail locations, hospitals, clinics, pharmacies, or local law enforcement facilities. Ask your pharmacist for more information on how to get rid of your medications safely.

Off-Label Uses

Elmiron is sometimes used "off-label" to treat mild knee osteoarthritis. "Off-label" means using a medication for a reason other than what it was approved for. A healthcare provider may prescribe off-label treatment if the decision is supported by scientific evidence or expert clinical experience.

How Long Does Elmiron Take to Work?

Elmiron can take at least three to six weeks to improve the symptoms of interstitial cystitis.

What Are the Side Effects of Elmiron?

This is not a complete list of possible Elmiron side effects, and others may occur. Your provider can advise you on side effects. If you experience other effects, contact your pharmacist or a healthcare provider. You may report side effects to the FDA at www.fda.gov/medwatch or 1-800-FDA-1088.

Common Side Effects

Some common side effects of Elmiron are:

  • Hair loss (alopecia)
  • Dizziness
  • Gastrointestinal symptoms (e.g., stomach pain, nausea, and diarrhea)
  • Heartburn
  • Headache
  • Rash
  • Moodiness or depression

Tell your healthcare provider if any of these symptoms are severe or do not go away.

Severe Side Effects

Call your healthcare provider immediately if you have serious side effects while you are taking Elmiron. Call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency.

There are some severe side effects of Elmiron. While these symptoms are uncommon, you should call your provider right away if you have signs of increased bleeding, such as:

  • Black, tarry stools or red blood in stools
  • Nosebleeds
  • Heavy gum bleeding
  • Unusual bruising or bleeding
  • Bloody or vomit or vomiting material that looks like coffee grounds

Pentosan polysulfate may cause side effects other than the ones listed here. Contact your provider if you have any unusual problems while taking this medication.

A severe allergic reaction to Elmiron is rare. However, get medical help immediately if you have any symptoms of a serious allergic reaction, including: 

  • Rash, itching, or swelling
  • Severe dizziness
  • Trouble breathing

Long-Term Side Effects

In some people, the long-term use of Elmiron causes pigmentary changes in the thin layer of tissue on the back wall of the eyeball that transmits images for the brain to perceive (retina). This is called pigmentary maculopathy.

Contact your healthcare provider if you notice any changes in your vision. Retinal examinations are recommended for people within six months of starting Elmiron.

Report Side Effects

Elmiron may cause other side effects. Call your healthcare provider if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your healthcare provider may send a report to the FDA's MedWatch Adverse Event Reporting Program or by phone (1-800-332-1088).

Dosage: How Much Elmiron Should I Take?

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The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage form (capsules):
    • For symptoms of interstitial cystitis:
      • Adults and children 16 years of age and older—100 milligrams (mg) 3 times a day for 3 months. Some patients may continue to take this medicine for another 3 months.
      • Children younger than 16 years of age—Use and dose must be determined by your doctor.


You may need to be more cautious while taking Elmiron if any of the following situations apply to you:

  • Liver issues: Elmiron has not been studied in people with decreased liver function. However, liver problems may affect how the medication is eliminated from the body. Before starting Elmiron, tell your healthcare provider if you have any problems with your liver. Extra monitoring might be needed.
  • Pregnancy: Talk to your healthcare provider if you are pregnant or plan to become pregnant while taking Elmiron. There is no evidence of fetal harm in humans from Elmiron, but this medication may only be prescribed if no other alternatives exist.
  • Breastfeeding: It is unknown whether this drug passes into human milk. Use caution while breastfeeding if you are taking Elmiron. Always ask your healthcare provider first.

Some health conditions may affect how you take Elmiron. Tell your healthcare provider if you have:

  • A personal or family history of retinal problems, aneurysms, or bleeding easily
  • Hemophilia (an inherited bleeding disorder)
  • Gastrointestinal conditions such as ulcers, polyps, or diverticulosis
  • Liver dysfunction

Missed Dose

If you miss a dose of Elmiron, take it as soon as you remember. If it is nearly time for your next dose, skip the missed dose. Take the following doses at a regular time. Do not take a double dose to make up for the missed one.

Overdose: What Happens If I Take Too Much Elmiron?

Overdoses have not been reported with Elmiron; an overdose on this medication is unlikely. Still, be mindful to only take the amount prescribed for you. Taking too much may increase the risk of side effects.

What Happens If I Overdose on Elmiron?

If you think you or someone else may have overdosed on Elmiron, call a healthcare provider or the Poison Control Center (1-800-222-1222).

If someone collapses or isn't breathing after taking Elmiron, call 911 immediately.


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It is very important that your doctor check your or your child's progress at regular visits to make sure this medicine is working properly. Blood tests may be needed to check for unwanted effects.

Check with your doctor right away if blurred vision, difficulty with reading, slower adjustment to low or reduced light, or any other change in vision occurs during or after treatment. Your doctor may want your eyes be checked by an ophthalmologist (eye doctor) and eye tests will be needed, especially within 6 months of starting treatment with this medicine.

This medicine can temporarily lower the number of platelets in your blood, which are necessary for proper blood clotting. Because of this, you may bleed longer than usual or get bruised more easily. If this occurs, there are certain precautions you can take to reduce the risk of bleeding:

  • Check with your doctor immediately if you notice any unusual bleeding or bruising, black, tarry stools, blood in the urine or stools, or pinpoint red spots on your skin.
  • Be careful when using a regular toothbrush, dental floss, or toothpick. Your medical doctor, dentist, or nurse may recommend other ways to clean your teeth and gums. Check with your medical doctor before having any dental work done.
  • Be careful not to cut yourself when you are using sharp objects such as a safety razor or fingernail or toenail cutters.
  • Avoid contact sports or other situations where bruising or injury could occur.

Make sure any doctor or dentist who treats you knows that you are using this medicine. You may need to stop using this medicine several days before having surgery or medical tests.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or non-prescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

What Are Reasons I Shouldn’t Take Elmiron?

Do not take Elmiron if you have known hypersensitivity to pentosan polysulfate or similar compounds, such as heparin (an anticoagulant used to decrease blood clotting) and low-molecular heparin.

What Other Medications Interact With Elmiron?

Elmiron is a relatively safe and well-tolerated drug, with few known drug-drug interactions. Still, it is essential to tell your healthcare provider about all prescription medications, over-the-counter (OTC) drugs, supplements, and herbal medicines you are taking.

Let them know if you are taking any other blood thinners. The following medications can increase your risk of bleeding if taken with Elmiron:

Ask your healthcare provider or pharmacist for a complete list of drug interactions that may occur with Elmiron.

What Medications Are Similar?

Elmiron is the only heparinoid drug that is approved by the Food and Drug Administration (FDA) to treat IC. Other medications belonging to this drug class, such as heparin, are used to treat various blood clotting disorders.

Frequently Asked Questions

  • What is Elmiron used for?

    Elmiron is a prescription medicine used to treat bladder pain or discomfort related to interstitial cystitis, a chronic bladder condition.

  • How does Elmiron work?

    Elmiron is thought to work by repairing the bladder lining to minimize leaks and reduce inflammation and pain.

  • What drugs should not be taken with Elmiron?

    Elmiron is relatively safe to take with other medications. However, blood thinners can increase the risk of bleeding. Before starting Elmiron, tell your healthcare provider if you are taking any other blood thinning medications.

  • How long does it take for Elmiron to work?

    After starting treatment with Elmiron, it may take three to six months before you see an improvement in the symptoms of IC.

  • What are the side effects of Elmiron?

    Common side effects of Elmiron include hair loss, dizziness, headache, gastrointestinal problems, and rash. You may also have abnormal liver function test results.

How Can I Stay Healthy While Taking Elmiron?

IC is a complex disease. Although not visible on the outside, its symptoms can be painful and difficult to manage. Bladder treatments aim to improve symptoms and overall quality of life.

Elmiron is the only drug that is approved to treat IC. While it can help reduce your symptoms, you may need to use other methods of relief as well. Certain lifestyle factors can aggravate or trigger symptom flare-ups. Try to avoid foods or drinks that seem to make your symptoms worse (for example, spicy foods, alcohol, or coffee).

Stressors such as anxiety or depression can also interfere with symptom relief. Consider seeking support groups for people who are also coping with IC and chronic pain. The Interstitial Cystitis Association offers resources like support communities online and in person.

Tell your healthcare provider if your IC symptoms worsen or do not improve. You may need to try a different therapy to find what works best for you.

Medical Disclaimer

Verywell Health's drug information is meant for educational purposes only and is not intended to replace medical advice, diagnosis, or treatment from a healthcare provider. Consult your healthcare provider before taking any new medication(s). IBM Watson Micromedex provides some of the drug content, as indicated on the page.

10 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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