Chronic Use of Elmiron Associated With Macular Disorders
In recent years, long-term use of Elmiron®, or pentosan polysulfate sodium (PPS), has been linked with macular disorders. Elmiron, manufactured by Jansen, is the only FDA-approved oral treatment for interstitial cystitis (IC). IC causes chronic pain in the bladder and pelvis area, and the condition affects more than 1 million people in the United States.
What Are Macular Disorders?
The macula is the central part of the retina located at the posterior pole of the eye. Located between the inferior and superior temporal arteries, the macula is the part responsible for providing central vision, detecting details, and controlling our ability to read.
Various problems can affect the macula, leading to macular disorders. The most common of these is macular degeneration, which is the primary cause of vision loss and affects more than 10 million people in the United States.
Macular degeneration occurs when the central portion of the retina wears down. Other common macular disorders are macular holes, macular edema, and myopic maculopathy. Several studies and case reports have linked Elmiron to macular diseases, especially pigmentary maculopathy or macular degeneration.
Studies Link Elmiron to Maculopathy
A case report published in the Journal of Ophthalmology in May 2018 linked pigmentary maculopathy to chronic exposure to pentosan polysulfate sodium. The report focused on six women who were being treated for interstitial cystitis and who developed significant vision problems. Most of the patients experienced difficulty adjusting to low light environments and difficulty reading.
Two patients had difficulty seeing close-up objects, and two others experienced blurry vision as the first symptom. One patient experienced partial vision loss, and another had distorted vision with straight lines appearing wavy. However, none of them had diagnoses of retinal problems in their medical history.
The only thing they had in common was the prolonged use of Elmiron. Five patients took 400mg of Elmiron daily, while one patient was taking a dose of 300mg daily. At least two patients used no other medications in their treatment.
In a follow-up study conducted at California-based Kaiser Permanente, three ophthalmologists found that about 25% of patients with long-term exposure to PPS exhibited clear signs of retinal damage. They also discovered that Elmiron toxicity could mimic other known macular disorders such as pattern dystrophy and age-related macular degeneration.
All the recent studies show that most affected patients were women with an average age of 60 years. The most common symptoms of Elmiron-associated macular disorders include:
- Dimming vision
- Difficulty reading
- Difficulty seeing objects close up
- Difficulty adjusting to the darkness
- Dark spots in the central field of vision
- Metamorphopsia (visual distortion causing linear objects to appear curved)
According to current study findings, Elmiron-induced maculopathy seems to be limited to patients using the medication. Patients using other types of treatment or medication haven’t experienced retinal issues. The studies show that patients taking Elmiron for three to 22 years are susceptible to this drug-induced macular disorder.
Recent data noted that susceptibility to Elmiron-associated maculopathy increased with the amount of Elmiron taken. Those taking 500 to 1,000 grams of Elmiron per day had an 11% risk of developing the condition, while those taking more than 1,500 grams daily dose had a 42% risk.
Elmiron-induced Macular Disorders Worsen Over Time
Some researchers point out that Elmiron-induced maculopathy could worsen for several years after the patient stops taking the drug. According to a case report published in Ophthalmic Surgery, Lasers and Imaging Retina in 2019, a 69-year-old woman had continued to experience deteriorating vision six years after halting the use of Elmiron.
In this case study, Harvard researchers explain that the woman first reported vision problems at 62 years of age. She complained of blurry vision and difficulty seeing in darkness. Doctors later diagnosed her with Elmiron-associated maculopathy.
While medical records indicated that she ceased using PPS at age 62, examinations conducted at age 67 and age 69 showed that her condition continued to worsen. The research findings show that Elmiron-related vision problems could continue to worsen even after the patient stops the medication.
Doctors and researchers behind recent studies advise patients to consult with their prescribing physicians to reevaluate whether the benefits of high-dose or long-term use of Elmiron outweigh the potential adverse effects on eye health. Patients should also undergo regular screening, imaging, and eye toxicity monitoring if they choose to continue taking Elmiron.
To help mitigate Elmiron’s effect on eye health, the FDA mandated an Elmiron label change in June 2020. The updated label included warnings about pigmentary maculopathy in the “Warnings and Precautions” and “Adverse Reactions” sections of the Elmiron drug label.