Skip to main content

Intravesical Agents for IC/BPS

Intravesical instillation is a cornerstone of second- and third-line therapy for interstitial cystitis / bladder pain syndrome (IC/BPS). DMSO (dimethyl sulfoxide) is the only FDA-approved intravesical agent for this indication. The 2022 AUA guideline lists DMSO, heparin, and / or lidocaine as intravesical treatment options (Statement 17) without imposing a hierarchy among them, and a wide range of additional agents — GAG-replenishment products (hyaluronic acid, chondroitin sulfate), botulinum toxin A, intravesical oxybutynin, intravesical pentosan polysulfate, and emerging sustained-release platforms — are used off-label with varying evidence.[1][2][3]

For the broader clinical condition and oral pharmacotherapy, see IC/PBS and Oral IC/BPS Agents. For the dedicated botulinum toxin article, see Botulinum Toxin.

Organizational Framework​

ClassAgentsMechanismAUA position
Anti-inflammatory / multimodalDMSO (Rimso-50)Anti-inflammatory, analgesic, collagen dissolution, muscle relaxant, mast-cell stabilizationOption (Grade C); FDA-approved[1]
Local anestheticLidocaine (± alkalinization)Direct urothelial anesthesiaOption (Grade B)[1]
GAG replenishmentHeparinRestores GAG layer, inhibits leukocytes, scavenges ROSOption (Grade C)[1]
GAG replenishmentHyaluronic acid (HA), chondroitin sulfate (CS), HA/CS comboGAG-layer restoration, anti-inflammatoryNot in AUA guideline; widely used in Europe[3][4][5][6]
Neuromuscular blockadeOnabotulinumtoxinA (intradetrusor)Inhibits ACh and ATP release from nerve and urotheliumOption (Grade C); later-line[1][14][15][16]
AnticholinergicOxybutyninReduces detrusor spasm; local anesthetic effectNot in AUA guideline; in 2025 Global Consensus[2][4]
GAG replenishmentPentosan polysulfate (intravesical)Reduces mucosal permeabilityNot in AUA guideline[7][17]
Vanilloid agonistsResiniferatoxin, capsaicinC-fiber TRPV1 desensitizationNot recommended[8][18]
ImmunomodulatoryBCGImmunological modulationNot recommended by AUA[4][7]
Combination cocktailsDMSO + heparin + steroid + lidocaine / bupivacaineMultimodalCommonly used in practice[1][11]

DMSO (Rimso-50) — the FDA-approved agent​

DMSO has been available since the 1970s and remains the reference intravesical therapy.[9]

Multiple mechanisms[4]​

  • Anti-inflammatory inhibition of inflammatory mediators
  • Direct analgesic effect
  • Collagen dissolution (may reduce mural fibrosis)
  • Detrusor smooth-muscle relaxation
  • Mast-cell stabilization (relevant to mast-cell–mediated IC/BPS pathophysiology)
  • Membrane permeation enhancer — rapidly absorbed across the bladder wall and enhances absorption of co-administered agents (key safety point for cocktails)

Dosing protocol (FDA label)[9]​

  • Formulation: 50% DMSO solution (50:50 with water)
  • Dose: 50 mL by catheter
  • Dwell time: ~ 15 minutes — longer dwell times produce significant pain[1]
  • Frequency: every 2 weeks until maximum symptomatic relief, then taper interval
  • Pre-treatment: intraurethral lidocaine jelly; oral analgesics or B&O suppository for bladder spasm
  • Severe cases: initial 2–3 treatments may need anesthesia (saddle block)

Efficacy​

A 2025 systematic review and meta-analysis (5 RCTs + 9 observational studies, 554 patients) found intravesical DMSO produced clinically meaningful improvements in IC symptom scores and pain.[10]

A 2023 RCT (n = 42, newly diagnosed IC/PBS) compared DMSO vs BTH (bupivacaine + triamcinolone + heparin) cocktail and found similar improvements at 6 weeks: ICSI reduced 29.5% (DMSO) vs 43% (BTH) (p = 0.15), with both groups showing significant gains in cystometric capacity.[11]

Adverse effects[9][10]​

  • Garlic-like taste within minutes of instillation, lasting hours
  • Garlic-like body / breath odor lasting up to 72 hours — a major patient-acceptance barrier
  • Transient chemical cystitis discomfort during instillation
  • Rare hypersensitivity (DMSO can liberate histamine)
  • Overall AE rate ~38% in meta-analysis, mostly mild

Required monitoring (FDA label)[9]​

  • Eye evaluation including slit lamp before treatment and periodically (lens opacities seen in animals at high chronic doses)
  • Liver function, renal function, CBC every ~6 months

Contraindications and cautions[9]​

  • Urinary tract malignancy — DMSO-induced vasodilation may be harmful
  • Pregnancy — animal teratogenicity at high doses
  • Drug interactions — potentiates absorption of co-administered drugs (the rationale for shorter dwell times in DMSO cocktails)

Lidocaine​

Mechanism: direct local anesthetic on the urothelium and submucosal afferents.[4]

Evidence: AUA Grade B — short-term symptom relief (< 2 weeks); benefit durability beyond a single instillation is limited.[1]

Practical caution: when combined with DMSO, DMSO enhances lidocaine absorption and can produce systemic toxicity (perioral numbness, tinnitus, dizziness, seizures, cardiac effects). Use shorter dwell times in DMSO cocktails and counsel patients on toxicity symptoms.[1][9]

Heparin​

Mechanism: heparin is a naturally occurring GAG that augments the urothelial mucopolysaccharide layer, inhibits leukocyte function, and scavenges reactive oxygen species — acting as a synthetic substitute for the deficient GAG barrier.[4][12]

Evidence (AUA Grade C): observational data show clinically significant symptom improvement; trials of heparin combined with alkalinized lidocaine show significant improvement vs placebo.[1]

Typical dosing:

  • 10,000–40,000 U heparin in 10–30 mL normal saline or sterile water
  • Dwell 30–60 minutes
  • Daily to 3×/week initially → weekly maintenance
  • Suitable for home self-instillation with patient training

Advantages: well tolerated, minimal local AEs, no garlic odor, supports long-term maintenance.

Intravesical Cocktails​

In practice, combinations are routinely used to leverage multiple mechanisms.[1][11]

"Recipe"CompositionDwellNotes
Classic DMSO cocktailDMSO 50 mL + heparin 10,000–40,000 U + hydrocortisone 100 mg (or triamcinolone 40 mg) + NaHCO₃ 44 mEq ± lidocaine 1–2% 10–20 mL15–20 minLimited by DMSO-induced pain and absorption-enhancement risk
Heparin–lidocaine (non-DMSO)Heparin 40,000 U + lidocaine 2% 8 mL + NaHCO₃ 8.4% 3 mL + saline to ~ 15 mL30–60 minBetter tolerated for home self-instillation
BTH cocktailBupivacaine 0.5% 10 mL + triamcinolone 40 mg + heparin 10,000 U + saline to ~ 30 mL30–60 minDMSO-free alternative; comparable to DMSO in head-to-head RCT[11]

Key practical points:

  • DMSO-containing cocktails get shorter dwells (15–20 min) because of pain and absorption-enhancement
  • Non-DMSO cocktails tolerate 30–60 min dwells and translate well to home self-instillation
  • Sodium bicarbonate alkalinizes the solution and improves lidocaine penetration[1]
  • Steroid (hydrocortisone or triamcinolone) provides local anti-inflammatory effect

GAG Replenishment Therapy (HA, CS, HA + CS)​

GAG-replenishment is built on the model that IC/BPS reflects urothelial GAG-layer disruption that allows urinary solutes to penetrate the wall and trigger inflammation.[12]

Hyaluronic acid (HA)​

  • HA influences barrier integrity through urothelial-cell interactions rather than purely restoring the luminal GAG layer[13]
  • A 2025 meta-analysis (30 studies) found HA / CS instillation significantly improved pain, voiding symptoms, and irritative symptoms in BPS patients; in RCTs, combined HA/CS showed better outcomes and lower infection rates than placebo or standard care (OR 0.42, 95% CI 0.25–0.49)[5]
  • Typical dose: 40 mg HA in 50 mL saline weekly × 4–6, then monthly maintenance
  • Widely used in Europe (Cystistat, Ialuril); not FDA-approved in the US for IC/BPS

Chondroitin sulfate (CS)​

  • GAG-layer replenishment with anti-inflammatory effect[4]
  • Network meta-analysis ranked CS as the safest intravesical agent (78.5% probability)[3]
  • Typical dose: 0.2% solution, 40 mL weekly × 6, then monthly

Combined HA + CS (Ialuril)​

  • A randomized open-label multicenter study (n = 110) compared HA/CS vs DMSO and found HA/CS as effective as DMSO with a more favorable safety profile (treatment-related AEs 1.35% vs 22.2%, p = 0.001), with greater pain reduction in the per-protocol population (mean VAS −44.77 vs −28.89, p = 0.019)[6]
  • Network meta-analysis ranked HA/CS second for ICSI improvement and first for VAS pain reduction[3]
  • Reported cost-effectiveness ICER for HA/CS vs DMSO: 3,735–8,003 €/QALY[6]

Botulinum Toxin A (intradetrusor)​

The dedicated Botulinum Toxin article covers OAB and NDO uses; the IC/BPS-specific notes:

  • AUA position: intradetrusor onabotulinumtoxinA may be administered after other treatments fail, with the patient willing to accept the possibility of clean intermittent self-catheterization (Option, Grade C)[1]
  • Mechanism in IC/BPS: inhibits ACh and ATP release from nerve and urothelium → reduces hypersensitivity, pain signaling, and involuntary contractions[14]
  • Efficacy — meta-analysis of 12 RCTs found significant improvements in ICSI (SMD −0.302), ICPI (SMD −0.430), and VAS pain (SMD −0.576); intratrigonal 100 U vs placebo achieved ≥ 50% pain reduction in 60% vs 22%[15][16]
  • Network meta-analysis ranked onabotulinumtoxinA highest for global response assessment improvement (probability 81.7%)[7]
  • Dose: 100 U in 10–30 mL saline, intradetrusor at 20–30 sites; injection sites vary across studies (trigonal, lateral, or posterior wall)[1]
  • AEs: dysuria, large PVR, need for CISC, UTI[1]
  • Decision point: shared decision-making is essential — short-term efficacy traded against the meaningful possibility of CISC[1]

Other Intravesical Agents​

Intravesical oxybutynin​

  • Anticholinergic with local anesthetic properties[4]
  • Cochrane review found oxybutynin instillation increased bladder capacity, reduced frequency, improved QoL, and had fewer dropouts — among the most promising results in the review[4]
  • Typical dose 5–10 mg in 20–30 mL saline; dwell 30 min
  • Listed in the 2025 Global Consensus update[2]

Intravesical pentosan polysulfate (PPS)​

  • Network meta-analysis: improves urinary frequency and urgency vs placebo; lidocaine combined with PPS yielded greater symptom relief than lidocaine alone[7][1]
  • Oral PPS is the only FDA-approved oral agent for IC/BPS — but PPS-associated pigmented maculopathy with chronic oral use has reshaped prescribing[17][1]

Bacillus Calmette-Guérin (BCG)​

  • Immunomodulation based on autoimmune theory[4]
  • Mixed evidence — Cochrane found a trend to less pain and fewer general symptoms; network meta-analysis suggested GRA improvement[4][7]
  • AUA does not recommend BCG for IC/BPS — risks of granulomatous cystitis and systemic BCG infection[1]

Vanilloid agonists (resiniferatoxin, capsaicin)​

  • TRPV1-mediated C-fiber desensitization[4]
  • The largest RCT (n = 163) of intravesical RTX found no improvement in symptoms, pain, urgency, frequency, nocturia, or void volume over 12 weeks; dose-dependent instillation pain[8]
  • A meta-analysis found RTX reduced bladder pain but did not improve frequency, nocturia, or incontinence[18]
  • A network meta-analysis paradoxically ranked low-dose RTX favorably, but this likely reflects small-study effects and heterogeneity[3][8]
  • Not recommended for routine clinical use[4]

Intravesical steroids (triamcinolone)​

  • Local anti-inflammatory; primarily used as a cocktail component (with DMSO or heparin)[4]
  • One RCT compared intravesical triamcinolone injection vs fulguration for Hunner lesions[19]
  • Typical cocktail dose: 40 mg triamcinolone acetonide

Emerging Therapies and Novel Delivery Systems​

Intravesical interferon​

A 2024 RCT (n = 52) found intravesical interferon produced significantly greater reductions in VAS pain, ICSI, and ICPI at 6 months than hyaluronic acid, with good tolerability — rationale supported by emerging evidence of viral involvement (BK / JC virus) in IC pathogenesis.[20]

Sustained-release platforms​

A major limitation of every intravesical agent is rapid drug clearance with voiding. Several sustained-release systems are in development:[2][21][22]

  • TRG-100 — sustained-release lidocaine + oxybutynin; pilot (n = 36) showed 3.2-point VAS reduction, 25.4% reduction in frequency, and 8.1-point reduction in O'Leary–Sant scores
  • Silk-elastinlike protein polymer (SELP) — temperature-responsive polymer that enhances GAG accumulation in urothelium and produces sustained 24-hour analgesia
  • Intravesical liposomes — under investigation for sustained delivery and barrier protection

Certolizumab pegol (anti-TNF) and antiviral approaches​

Anti-TNF biologics and intravesical antivirals are in early-phase clinical investigation; phenotyping by BK virus status may eventually guide selection.[17][20]

Comparative Effectiveness Summary​

A network meta-analysis (Zhang et al.) ranked intravesical agents by global response assessment:[7]

  1. OnabotulinumtoxinA — highest probability of being best (81.7%)
  2. BCG — significant GRA improvement (but not recommended for safety reasons)
  3. PPS — improved frequency and urgency
  4. Lidocaine, CS, oxybutynin — variable

The pragmatic interpretation: modest effect sizes across the board, no single agent dominant, treatment is individualized, and almost every patient ultimately benefits from a combination plus behavioral/oral therapy.[23]

Clinical Positioning​

  • DMSO is the FDA-approved option but garlic odor and the 15-minute dwell limit acceptability — best suited to in-office induction series (every 2 weeks × 6, then taper)[1][9]
  • Heparin–lidocaine cocktails are workhorse agents for home self-instillation because they are well tolerated, allow long dwells, and avoid DMSO odor[1]
  • HA / CS (Ialuril) — as effective as DMSO with a markedly better safety profile in head-to-head RCT; the practical European default; not FDA-approved in the US[5][6]
  • OnabotulinumtoxinA is reserved for refractory disease and only for patients willing to accept CISC; counsel and document[1]
  • Resiniferatoxin / capsaicin are not appropriate for clinical use[4][8]
  • DMSO enhances absorption of co-administered drugs — use shorter dwells and watch for lidocaine toxicity in DMSO cocktails[1][9]
  • Hunner-lesion phenotype is a separate disease — fulguration / triamcinolone injection of the lesion outperforms generic intravesical therapy and should be considered before extended courses of generic instillations[19]

See Also​

References​

1. Clemens JQ, Erickson DR, Varela NP, Lai HH. "Diagnosis and treatment of interstitial cystitis/bladder pain syndrome." J Urol. 2022;208(1):34–42. doi:10.1097/JU.0000000000002756

2. Buford K, Peters KM, Riedl C, et al. "Global consensus on interstitial cystitis/bladder pain syndrome: an update on therapeutic treatments." Neurourol Urodyn. 2025. doi:10.1002/nau.70106

3. Liu S, Zhang C, Peng L, Lu Y, Luo D. "Comparative effectiveness and safety of intravesical instillation treatment of interstitial cystitis/bladder pain syndrome: a systematic review and network meta-analysis of randomized controlled trials." Int Urogynecol J. 2021;32(5):1061–1071. doi:10.1007/s00192-020-04490-3

4. Dawson TE, Jamison J. "Intravesical treatments for painful bladder syndrome / interstitial cystitis." Cochrane Database Syst Rev. 2007;(4):CD006113. doi:10.1002/14651858.CD006113.pub2

5. Corona G, Capogrosso P, Baldini S, et al. "Hyaluronic acid and chondroitin sulphate instillation in chronic bladder diseases: a meta-analysis." BJU Int. 2025. doi:10.1111/bju.70016

6. Cervigni M, Sommariva M, Tenaglia R, et al. "A randomized, open-label, multicenter study of the efficacy and safety of intravesical hyaluronic acid and chondroitin sulfate versus dimethyl sulfoxide in women with bladder pain syndrome / interstitial cystitis." Neurourol Urodyn. 2017;36(4):1178–1186. doi:10.1002/nau.23091

7. Zhang W, Deng X, Liu C, Wang X. "Intravesical treatment for interstitial cystitis / painful bladder syndrome: a network meta-analysis." Int Urogynecol J. 2017;28(4):515–525. doi:10.1007/s00192-016-3079-4

8. Payne CK, Mosbaugh PG, Forrest JB, et al. "Intravesical resiniferatoxin for the treatment of interstitial cystitis: a randomized, double-blind, placebo controlled trial." J Urol. 2005;173(5):1590–1594. doi:10.1097/01.ju.0000154631.92150.ef

9. US Food and Drug Administration. RIMSO-50 (dimethyl sulfoxide) — prescribing information. Updated 2021-03-17.

10. Li HR, Shen SH, Gao XS, Peng L, Luo DY. "The efficacy and safety of dimethyl sulfoxide into the bladder for the treatment of interstitial cystitis / bladder pain syndrome: a systematic review and meta-analysis." Neurourol Urodyn. 2025;44(5):1036–1046. doi:10.1002/nau.70036

11. Moss NP, Chill HH, Sand PK, et al. "A prospective, randomized trial comparing intravesical dimethyl sulfoxide (DMSO) to bupivacaine, triamcinolone, and heparin (BTH), for newly diagnosed interstitial cystitis / painful bladder syndrome (IC/PBS)." Neurourol Urodyn. 2023;42(3):615–622. doi:10.1002/nau.25142

12. Wyndaele JJJ, Riedl C, Taneja R, et al. "GAG replenishment therapy for bladder pain syndrome / interstitial cystitis." Neurourol Urodyn. 2019;38(2):535–544. doi:10.1002/nau.23900

13. van Ginkel CJ, Baars CDM, Tiemessen DM, et al. "Hyaluronic acid: function and location in the urothelial barrier for bladder pain syndrome / interstitial cystitis, an in vitro study." PLoS One. 2025;20(2):e0318277. doi:10.1371/journal.pone.0318277

14. Lin YH, Chiang BJ, Liao CH. "Mechanism of action of botulinum toxin A in treatment of functional urological disorders." Toxins. 2020;12(2):E129. doi:10.3390/toxins12020129

15. Giannantoni A, Gubbiotti M, Bini V. "Botulinum neurotoxin A intravesical injections in interstitial cystitis / bladder painful syndrome: a systematic review with meta-analysis." Toxins. 2019;11(9):E510. doi:10.3390/toxins11090510

16. Pinto RA, Costa D, Morgado A, et al. "Intratrigonal onabotulinumtoxinA improves bladder symptoms and quality of life in patients with bladder pain syndrome / interstitial cystitis: a pilot, single center, randomized, double-blind, placebo controlled trial." J Urol. 2018;199(4):998–1003. doi:10.1016/j.juro.2017.10.018

17. Chermansky CJ, Guirguis MO. "Pharmacologic management of interstitial cystitis / bladder pain syndrome." Urol Clin North Am. 2022;49(2):273–282. doi:10.1016/j.ucl.2022.01.003

18. Guo C, Yang B, Gu W, et al. "Intravesical resiniferatoxin for the treatment of storage lower urinary tract symptoms in patients with either interstitial cystitis or detrusor overactivity: a meta-analysis." PLoS One. 2013;8(12):e82591. doi:10.1371/journal.pone.0082591

19. Imamura M, Scott NW, Wallace SA, et al. "Interventions for treating people with symptoms of bladder pain syndrome: a network meta-analysis." Cochrane Database Syst Rev. 2020;7:CD013325. doi:10.1002/14651858.CD013325.pub2

20. Shen SH, Peng L, Zeng X, et al. "Intravesical interferon therapy vs hyaluronic acid for pain among female individuals with interstitial cystitis: a randomized clinical trial." JAMA Netw Open. 2024;7(4):e244880. doi:10.1001/jamanetworkopen.2024.4880

21. Jensen MM, Jia W, Schults AJ, et al. "Temperature-responsive silk-elastinlike protein polymer enhancement of intravesical drug delivery of a therapeutic glycosaminoglycan for treatment of interstitial cystitis / painful bladder syndrome." Biomaterials. 2019;217:119293. doi:10.1016/j.biomaterials.2019.119293

22. Raisin G, Dothan D, Perez D, et al. "Open label, pilot evaluation of the safety and efficacy of intravesical sustained release system of lidocaine and oxybutynin (TRG-100) for patients with interstitial cystitis / bladder pain syndrome, overactive bladder and patients with retained ureteral stents following endourological interventions." Urology. 2023;178:42–47. doi:10.1016/j.urology.2023.05.016

23. Dimitrakov J, Kroenke K, Steers WD, et al. "Pharmacologic management of painful bladder syndrome / interstitial cystitis: a systematic review." Arch Intern Med. 2007;167(18):1922–1929. doi:10.1001/archinte.167.18.1922