Elmiron, or sodium pentosan polysulfate sodium, was first approved by the U.S. Food and Drug Administration in 1996 to treat pain from a bladder condition known as interstitial cystitis. Recent studies, however, have shown an association between long-term use of Elmiron and permanent vision damage.

Interstitial cystitis affects more than a million people in the U.S.—most of whom are women—causing chronic pain in the bladder and pelvis. While several treatments are available, Elmiron is the only oral medication that’s FDA approved to treat interstitial cystitis, despite its history of limited effectiveness. While most eye doctors are aware of these new vision concerns, many have never seen it within their practice.

The only other FDA-approved medication option for interstitial cystitis, RIMSO-50 (dimethylsulfoxide), is administered directly into the bladder, usually by a catheter in a process known as intravesical therapy. 

Elmiron: Questions About Safety and Effectiveness

Elmiron may be the only FDA-approved oral medication to treat interstitial cystitis, but research has shown that it’s only effective for one out of three people. 

In fact, a 2015 study showed Elmiron to be no more useful than a placebo and the study itself was terminated due to a lack of positive results. Other studies have yielded slightly more positive findings, and fortunately, there are other medications, such as amitriptyline that are more commonly prescribed today. Amitriptyline is prescribed for use to treat depression, but has been used off-label, meaning without FDA approval to treat urinary pain and urgency. 

The FDA clinical trials that led to Elmiron’s official approval to treat interstitial cystitis tested its use up to a year, but because patients must continue on Elmiron to prevent symptoms from returning, many have been on the drug for much longer. However, these long term effects haven’t been studied, and vision concerns didn’t show up on the list of adverse reactions back then. On June 16 Janssen Pharmaceuticals added a warning that Elmiron can cause pigmentary maculopathy in long-term users.

The Link Between Elmiron and Vision Damage

The relationship between Elmiron and maculopathy was first reported in 2018. A small case study of six patients who had experienced vision changes after being diagnosed with interstitial cystitis reported they took Elmiron for an average of 15 years. Difficulty reading and seeing in the dark were the main complaints. Later, a larger study of 35 patients was conducted that helped verify the association between maculopathy and Elmiron use. Many patients had been already diagnosed with age-related macular degeneration (ARMD). 

For those not familiar with maculopathies, it helps to understand the role the macula plays in our vision. Located on the back of the eye in the center of the retina, the macula is the area responsible for our sharpest center vision that helps us see fine detail and color in order for us to do things such as read and drive a car. Any damage to it can cause noticeable changes to our vision, which is often irreversible. While maculopathy is a generic term for a disease of the macula, pigmentary maculopathy is a particular type of maculopathy associated exclusively with long-term Elmiron use. 

Dr. Nieraj Jain, assistant professor of ophthalmology at Emory University School of Medicine, who specializes in vitreoretinal surgery and ophthalmic genetics, was involved in the early research for Elmiron maculopathy. According to Jain, the pattern of change in the macula can be subtle at first sight, but in using modern imaging techniques, ophthalmologists can see abnormal changes that stand out. 

As a retina specialist, Jain’s job is to take information from general exams and imaging tests and put a diagnosis together. 

“Particularly in earlier disease stages we see spots of pigmentation in the macula — yellowish deposits that appear to be underneath the retina,” he  told MedTruth. “In more advanced stages of disease we sometimes see a loss of tissue within the macula, which we refer to as atrophy.” 

Symptoms that have been reported include blurry vision, difficulty seeing in the dark, and, in advanced stages, blind spots. 

Jain believes those who are now coming forward with vision concerns have more severe symptoms. Once there is a greater awareness and more people are having their eyes checked, providers may find milder forms or those who may not have symptoms at all.  

Early stage pigmentary maculopathy, or PPS maculopathy, as it’s also called, can be hard to separate from age-related macular degeneration, which is a challenge to ophthalmologists such as Jain, because both can appear to affect people in similar demographics. According to Jain, both pigmentary  maculopathy and age-related macular degeneration occur most commonly in white people in their middle to late years.   

Testing For Pigmentary Maculopathy

When it comes to pigmentary maculopathy, early detection is key to preventing long-term vision damage. The best method is prevention, and Jain explained that patients who are on Elmiron should have a screening eye exam, as well as be taking the lowest necessary dose to control their symptoms. How often these exams are needed should be left up to each patient’s  provider. 

“What we do here at Emory is annual eye exams for all patients taking the drug out of an abundance of caution,” Jain said.

Most eye doctors have the appropriate equipment to use to check for this kind of damage. If the patient has any visual issues, according to Jain, a complete exam should be performed, including a dilated fundus exam. This exam looks at the back of the eye and involves dilating the pupils with eye drops to help see the retina better. The eye doctor can then examine the eyes through several lenses with a bright light to see if there is evidence of damage to the macula. 

It’s important to let your doctor know if you are taking Elmiron to treat your interstitial cystitis or have done so in the past. Jain cautions, however, that the word is still getting out. It’s possible that because research is still being conducted, eye doctors may not be aware of the concern. 

“I’ve had many patients take our paper to their ophthalmologist and it seems ophthalmologists have been pretty responsive when they see the paper,” he said. 

Jain also suggests requesting a referral to a retina specialist if you or a family member think there’s still an undetected concern. The most important thing you can do is let your eye doctor know as soon as you suspect an issue so appropriate testing can begin.