Alternatives to RIMSO-50 If You Can't Fill Your Prescription

RIMSO-50 (dimethyl sulfoxide) is the only FDA-approved bladder instillation therapy for interstitial cystitis (IC/BPS). When it becomes unavailable or inaccessible, patients are left asking: what else can I do? The good news is that there are several evidence-supported alternatives — both bladder instillations and oral medications — that your urologist can consider.

This guide covers the most widely used alternatives to RIMSO-50, how they work, and what to discuss with your provider.

First: Consider the Generic Dimethyl Sulfoxide

Before exploring other drug classes, it is worth noting that Sandoz manufactures a generic dimethyl sulfoxide 50% intravesical solution that is bioequivalent to RIMSO-50. If the problem is simply that brand-name RIMSO-50 is out of stock, the generic may be available. Ask your urologist to check with their specialty distributor for the Sandoz product.

Intravesical Alternatives to RIMSO-50

If DMSO is truly unavailable, these bladder instillation therapies are commonly used alternatives:

1. Intravesical Heparin

Heparin is an anticoagulant that, when instilled into the bladder, acts as an anti-inflammatory agent and may help repair the damaged glycosaminoglycan (GAG) layer of the bladder wall — a key factor in IC pain. Unlike RIMSO-50, heparin instillations are sometimes prescribed for self-administration at home, which can be convenient for patients with frequent treatment needs.

Research suggests heparin maintenance instillations can reduce the relapse rate after DMSO therapy — in one study, patients maintained with monthly heparin had a 20% relapse rate versus 52% for those who received DMSO alone without maintenance. This makes heparin a reasonable bridge or complement to RIMSO-50 therapy.

2. Intravesical Lidocaine Cocktails

Alkalinized lidocaine (lidocaine with sodium bicarbonate) is a commonly used off-label bladder instillation for IC. Lidocaine is a local anesthetic that can numb the bladder lining and reduce pain and urgency. In some cases, heparin, steroids, or other agents are added to create a "bladder cocktail." These cocktails can sometimes be self-administered at home on a daily or three-times-weekly schedule, making them highly convenient for patients.

3. Bupivacaine, Triamcinolone, and Heparin (BTH) Cocktail

A combination of bupivacaine (a long-acting local anesthetic), triamcinolone (a corticosteroid), and heparin (BTH) has been studied as a direct comparator to DMSO. A 2020 randomized trial found that both DMSO and BTH provided meaningful improvements in IC symptoms and bladder capacity — though DMSO appeared to provide greater improvement in bladder pain specifically. For patients who cannot access DMSO, the BTH cocktail is a well-supported alternative.

Oral Medication Alternatives for Interstitial Cystitis

If bladder instillation therapy is not available at all, oral medications can provide meaningful symptom control:

4. Elmiron (Pentosan Polysulfate Sodium)

Elmiron (pentosan polysulfate sodium) is the only oral medication FDA-approved specifically for interstitial cystitis. It is thought to work by restoring the protective mucus layer of the bladder wall. Elmiron takes time — patients typically need 2–4 months before feeling pain relief, and up to 6 months for a reduction in urinary frequency. Note that long-term use has been associated with a rare eye condition called pigmentary maculopathy; patients on Elmiron should receive regular eye exams.

5. Amitriptyline (Tricyclic Antidepressant)

Amitriptyline is a tricyclic antidepressant used off-label for IC that can help relax the bladder, block pain signals, and reduce urinary urgency. It is typically started at a low dose (10–25 mg at bedtime) and titrated up as needed. The AUA IC guidelines list tricyclic antidepressants as a recommended treatment option.

6. Antihistamines

Antihistamines such as hydroxyzine (Vistaril) and loratadine (Claritin) can help reduce urinary urgency and frequency in some IC patients. They are thought to work by stabilizing mast cells, which are believed to play a role in IC inflammation. These are well-tolerated and widely available.

7. NSAIDs and Pain Management

Nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen or naproxen sodium can help manage pain during periods when instillation therapy is unavailable. While they do not treat the underlying condition, they can provide meaningful short-term symptom relief while RIMSO-50 is sourced.

Non-Drug Options to Consider

While you work to secure RIMSO-50, non-pharmacological approaches can help manage symptoms:

Pelvic floor physical therapy: A trained pelvic floor PT can address muscle tension and connective tissue restrictions that contribute to IC pain.

Dietary modifications: Avoiding IC trigger foods (coffee, alcohol, citrus, spicy foods, artificial sweeteners) can significantly reduce flares for many patients.

Stress reduction: Stress is a known IC trigger. Meditation, yoga, and cognitive behavioral therapy have been shown to improve IC outcomes.

Don't Give Up on Finding RIMSO-50

While alternatives can bridge gaps in care, RIMSO-50 remains the gold-standard FDA-approved intravesical therapy for IC. If your clinic is struggling to locate it, consider using medfinder — a service that contacts pharmacies on your behalf to find which ones have RIMSO-50 in stock near you. medfinder texts you the results, so you spend less time calling and more time focusing on your health.

For more tips on locating the medication, see: How to Find RIMSO-50 in Stock Near You.