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Antimitotics and Antifibrotics

Antimitotic and antifibrotic adjuncts to endoscopic urethral stricture management target the pathologic wound-healing cascade of fibroblast proliferation, collagen deposition, and spongiofibrosis that drives recurrence after internal urethrotomy (IU) and dilation. Mitomycin C (MMC) has a favorable pooled recurrence signal. Paclitaxel-coated balloon catheters (Optilume) have FDA approval for adult men with obstructive urinary symptoms associated with anterior urethral strictures ≤3 cm.[1][2][3][37]

This article is the hub for MMC, paclitaxel DCBs, and related antimitotic / antifibrotic adjuncts (HA/CMC, PRP, tamoxifen, and preclinical agents). For intralesional corticosteroid adjuncts (triamcinolone), which are mechanistically distinct and covered separately, see Intralesional corticosteroids. For PRP-specific detail beyond this article, see Platelet-rich plasma. For the clinical condition, see Urethral stricture.

Why adjuncts are needed​

Internal urethrotomy and dilation are commonly performed, but outcomes depend on stricture selection. A 2016 review reported 0–9% long-term success across endoscopic series, including 9% after initial DVIU at 1–3 years.[4] EAU 2026 reports up to 77% five-year stricture-free survival for selected primary, single, short (<2 cm), nonobliterative bulbar strictures and weakly recommends DVIU or dilation for that group.[36] Recurrence is driven by pathologic wound healing: excessive fibroblast proliferation, collagen deposition, and spongiofibrosis.[2] The AUA Urethral Stricture Disease Guideline Amendment 2023 states that clinicians may endoscopically inject pharmacologic agents at the time of direct visual internal urethrotomy (DVIU) to reduce recurrence risk, though the evidence remains limited.[3]

Pang 2021 European Urology systematic review and meta-analysis identified 26 studies of 13 adjuncts; its meta-analysis of 13 RCTs (859 men) found lower recurrence with an adjunct versus none (OR 0.37; 95% CI 0.27–0.50; p < 0.001), although most studies had high risk of bias. Agent-specific signals:[1]

AgentIntralesional ORComment
Mitomycin C0.23 (0.11–0.48)Lowest intralesional versus-control OR reported in Pang[1]
Paclitaxel DCBNot intralesional; not pooled in Pang’s RCT meta-analysisROBUST III RCT reported separately; FDA-approved[1][18][37]
CorticosteroidsModest benefitSee Intralesional corticosteroids
CaptoprilSignal present; 61% urethral pruritus at instillationTolerability problem

Mitomycin C — the best-studied antifibrotic adjunct​

Mechanism​

MMC is an alkylating agent derived from Streptomyces caespitosus that cross-links DNA, inducing fibroblast apoptosis and inhibiting fibroblast proliferation and collagen synthesis.[5][6] In a small rat urethral-injury study, MMC reduced urothelial proliferation and DNA-damage markers while increasing DNA-repair markers; the authors proposed that this might permit re-epithelialization. MMC is a cytotoxic DNA-crosslinking drug; extravasation and tissue injury remain clinically important.[7]

Urethral stricture evidence​

StudynFinding
Mazdak 2007 RCT40Recurrence at 6 mo 10% MMC vs 50% control (p = 0.006) — the anchor RCT[8]
Irdam 2019 meta311 reported (4 studies; randomization methods incompletely reported)Random-effects RR 0.41 (95% CI 0.25–0.68; p < 0.001) for recurrence[9]
Farrell 201744 recurrent bulbar / bulbomembranous (all prior failures)At median 25.8 mo, 33/44 (75%) needed no further surgery after one DVIU + MMC (non-radiation 21/26, 80.8%; radiation 12/18, 66.7%). Four elected urethroplasty after recurrence; the other seven underwent repeat DVIU + MMC, leaving 37/40 (92.5%) without further surgery in the endoscopic pathway[10]
Farrell 201537 recurrent stricture / BNC75.7% no further surgery at 23 mo; non-RIS 84.6% vs RIS 54.5%[11]

Bladder-neck contracture and VUAS evidence​

StudyPopulationFinding
Vanni 201118 recurrent BNC72% patent after 1 procedure; 89% after 2 at median 12 mo follow-up[12]
Rozanski 2021 multi-institutional86 recurrent BNC / VUAS65% after 1 procedure, 83% after 2, and 90% cumulative after allowing 3 or more at median 21.1 mo; overall success non-radiated 94% vs radiated 76% (p = 0.04)[13]
Sourial 201729 recurrent post-RP VUAS79% patent at 12 mo after single MMC + dilation; 86% with salvage injection; 20/29 (69%) opted for anti-incontinence surgery, and all 20 were cured or improved at median 58 mo[14]
TURNS — Redshaw 2015 (cautionary)Multicenter BNC cohort; 55/66 analyzed after ≥3 mo cystoscopic follow-up32/55 (58%) resolution after 1 procedure at median 9.2 mo — lower than single-center series; 4/55 (7%) MMC-related serious adverse events (3 needing or planning cystectomy)[15]

The AUA 2023 guideline specifically notes "conflicting data about the utility of Mitomycin-C for the treatment of recurrent vesicourethral stenosis, with further study necessary to validate its use."[3]

Historical study protocols — not standardized prescribing​

EAU 2026 gives a weak recommendation to use intralesional injections only within clinical trials because drug, dose, volume and technique remain uncertain.[36] For posterior stenosis, MMC injection has been associated with necrosis and fistula; EAU strongly recommends against deep 6- and 12-o’clock DVIU incisions for VUAS or radiation-induced BMS and against endoluminal treatment of completely obliterated VUAS, BMS, or BNS.[15][36]

ProtocolDose / concentrationInjection sitesPost-procedure
Farrell / Levine10 mL of 0.4 mg/mL (4 mg total) in 0.2–0.4 mL aliquotsAt each cold-knife incision site (12, 3, 9 o'clock)CIC × 1 month[10][11]
Vanni / Buckley0.3–0.4 mg/mLTri- or quadrant cold-knife incisionsVariable[12]
Klein / Rusilko2 mg total in 5 mL sterile water5 and 7 o'clock incision sitesFoley catheter[16]
SourialMMC at 3, 6, 9 o'clockFollowed by dilation to 26FCystoscopic follow-up[14]
Mazdak original RCT0.1 mg submucosalAt urethrotomy siteStandard[8]

Safety​

  • Farrell’s 44-patient 2017 series (median 25.8 months) reported no long-term complications attributable to MMC.[10] The earlier 37-patient series (median 23 months) reported no significant morbidity.[11] Rozanski’s 86-patient series (median 21.1 months) reported no long-term complications.[13]
  • TURNS BNC series. Four of 55 analyzed patients (7%) had MMC-related grade 3 events after bladder-neck incision: two cases of osteitis pubis, one bladder-neck necrosis, and one rectourethral fistula; three needed or were planning cystectomy.[15][36]
  • Carcinogenicity concern. Mitomycin cross-links DNA, and its intravenous-product label reports increased tumor incidence in rats and mice; malignant transformation risk after local urethral injection is unknown.[40]
  • FAERS pharmacovigilance identified a bladder-perforation reporting signal for mitomycin.[17]

Paclitaxel drug-coated balloons (Optilume)​

Mechanism​

Paclitaxel stabilizes microtubules, leading to cell-cycle arrest, inhibited fibroblast proliferation and reduced collagen deposition. The Optilume DCB combines mechanical dilation with local paclitaxel delivery to a dilated stricture segment, preventing the usual post-dilation restenosis cascade.[18][19]

FDA status and guideline positioning​

  • FDA-approved for anterior urethral strictures (adult men; PMA P210020). The label contraindicates use in patients with hypersensitivity to paclitaxel or structurally related compounds, or a urologic implant such as a penile implant or artificial urinary sphincter; an active UTI must resolve before treatment. Men should abstain from sex or use condoms for 30 days; those with partners of childbearing potential should use highly effective contraception and avoid fathering a child for at least six months[37]
  • Label technique: place a 0.038-inch guidewire across the stricture, hold the uninflated balloon in position at least 60 seconds to hydrate the coating, then inflate to the size-specific rated burst pressure (8 to 12 atm across the 18 to 36 Fr balloons) for at least 5 minutes, never exceeding that pressure; fully deflate the balloon before withdrawal.[37]
  • AUA 2023 guideline amendment: surgeons may offer dilation or DVIU combined with a DCB for recurrent bulbar urethral strictures <3 cm [3]
  • EAU 2026: a strong recommendation to offer a paclitaxel DCB for a short (<3 cm) bulbar stricture recurring after at least two endoscopic treatments in patients unfit for or declining urethroplasty. Evidence for other sites (penile, membranous, bladder neck, VUAS), longer strictures, first-time strictures or prior urethroplasty is too limited for recommendations, and paclitaxel is detectable in semen for up to six months[36]

Key evidence​

Trialn / DesignFinding
ROBUST III RCT (Elliott 2022)127 recurrent anterior strictures <3 cm1-year freedom from reintervention 83.2% DCB vs 21.7% control (p < 0.0001); 6-month anatomic success (16 Fr scope or 14 Fr catheter passes) 74.6% vs 26.8%, complete-case analysis[18]
ROBUST III 3-year (Srikanth 2025)DCB arm of the same cohort; 56 in the three-year IPSS analysisAt 3 years, 71.9% Kaplan–Meier freedom from reintervention and 27/56 (48%) with at least 30% IPSS improvement without reintervention; no contemporaneous three-year randomized control[20]
TURNS real-world (Patel 2025)319 analyzed (260 anterior, 59 posterior; patients without follow-up or maintained on intermittent catheterization excluded); median follow-up 5.7 moAt 1 y, functional recurrence-free survival was 78.4% anterior / 75.8% posterior, but anatomical recurrence-free survival was 66.4% / 59.4%, respectively (Kaplan–Meier); hypospadias repair (HR 5.21) and a 24F/3 cm DCB (HR 3.64) predicted recurrence of any kind[21]
FIRST-CARE RCT (protocol 2026)Ongoing — treatment-naïve bulbar strictures ≤3 cmPrimary endpoint: freedom from reintervention at 12 months — tests Optilume as first-line rather than recurrent-stricture therapy[22]

For device-specific technical detail, see Drug-coated balloon therapy.

Hyaluronic acid / carboxymethylcellulose (HA/CMC)​

Mechanism: biophysical barrier gel that separates injured tissue surfaces, reduces adhesion formation, and modulates the wound-healing environment. Not a direct pharmacologic antifibrotic.

Evidence​

  • Chung 2013a multicenter RCT (n = 120 enrolled, 101 analyzed; post-EIU): recurrence at 24 wk 9.4% HA/CMC versus 22.9% control (p = 0.029); at 1 mo, lower VAS pain scores (0.67 versus 3.60; p < 0.001)[23]
  • Chung 2013b multicenter RCT (n = 180 enrolled, 161 analyzed; post-TURP): stricture incidence 1.3% (1/80) versus 8.6% (7/81) control; lower pain[24]
  • Kim 2025 NIUS-delivered HA versus conventional HA injection in 192 men after TURBT (multicenter RCT): higher day-1 patient satisfaction and less pain at placement; at 90 days, grade 1 cystoscopic narrowing was 3.9% versus 27.1%, but grade 2 narrowing requiring dilation was 1.3% versus 1.4% (45 missing 90-day surveillance)[25]

Systematic reviews classify HA/CMC alongside MMC as the best-supported adjuncts, with low to intermediate risk of bias.[2]

Platelet-rich plasma (PRP)​

Mechanism: Autologous PRP contains concentrated growth factors (PDGF, TGF-β, VEGF) proposed to support organized tissue healing.[26][27] In rat urethral-injury models, PRP reduced mucosal inflammation, edema and spongiofibrosis and brought the collagen I:III ratio toward uninjured controls.[26][27]

Evidence​

  • Rezaei 2019 RCT (87 men with symptomatic bulbar strictures randomized) of IU plus submucosal PRP versus IU plus saline: among assessed men, 12-mo recurrence was 9.09% versus 26.82% (p = 0.032); at 24 mo, recurrence was 9/41 (21.95%) versus 18/41 (43.90%). The two-year significance is unresolved; the indexed abstract prints p = 0.34, whereas EAU reports p = 0.034[28]
  • Animal studies confirm reduced mucosal inflammation, spongiofibrosis, and edema; normalized collagen-I:III ratio[26][27]

See Platelet-rich plasma for the broader PRP / PRF platform.

Oral systemic adjuncts​

  • Tamoxifen. SERM with antifibrotic effects in a rat renal-fibrosis model (reduced TGF-β1 and collagen expression); its urethral mechanism and estrogen-receptor dependence remain uncertain.[29] Included in the Pang 2021 meta (n = 30) as an adjunct to IU; limited data. AEs observed in the small stricture series: mild gynecomastia (6.7%) and GI effects (6.7%); systemic tamoxifen also carries thromboembolism risk, unquantified for short stricture regimens[1][38]
  • Deflazacort. Oral corticosteroid; n = 36 in the meta-analysis; very limited evidence[1]

Preclinical and early-clinical agents​

AgentEvidenceStatus
Captopril (intraluminal ACE inhibitor)n = 37 clinical — 61% pruritus limits tolerability[1]Clinical but poorly tolerated
Bevacizumab (anti-VEGF)Rabbit model: inhibits fibrosis comparably to MMC[30]Preclinical
5-FluorouracilRabbit model: comparable antifibrotic to MMC[30]Preclinical
Pirfenidone (nanoparticle-loaded catheter)Rabbit model: reduced fibrosis; TGF-β1 inhibition[31]Preclinical delivery platform
Wnt/β-catenin inhibitors (ICG-001, PRI-724)Rat model: reduced collagen I and α-SMA[32]Preclinical
Glycyrrhizic-acid biogel scaffoldRabbit model: M2 macrophage polarization, reduced pro-inflammatory cytokines[33]Preclinical
Protein-nanofilm drug-eluting cathetersECM-homeostasis modulation; reduced collagen + enhanced MMP-1 degradation[34]Preclinical drug-delivery platform

Combination regimens​

Reported in the Pang 2021 systematic review:[1]

  • Triamcinolone plus MMC plus hyaluronidase (n = 103; optical internal urethrotomy cohort): combines anti-inflammatory, antifibrotic, and tissue-penetration mechanisms[1]
  • Triamcinolone plus MMC plus hyaluronidase plus N-acetyl cysteine (n = 50; holmium laser urethrotomy cohort): adds antioxidant and mucolytic properties[1]

Head-to-head comparisons between combination and single-agent regimens are lacking. The review's randomized meta-analysis did not include these combinations.

Corticosteroids — pointer only​

Triamcinolone and other corticosteroid adjuncts are covered fully in Intralesional corticosteroids. Summary pointers relevant here:

  • Zhang 2014 8-RCT meta: steroids prolong time to recurrence (10.14 versus 5.07 months) but effect wanes over time[35]
  • Pang 2021 reported separate versus-control estimates for MMC and steroid regimens; it did not compare them directly[1] -Topical corticosteroids used with self-dilatation or for LS are distinct from intralesional post-DVIU injections.[36]

Comparative summary​

AgentRouteMechanismBest evidenceRecurrence signalKey limitation
Mitomycin CIntralesional / intraluminalDNA cross-link → fibroblast apoptosisPang 2021 meta; Mazdak RCT; Farrell seriesIntralesional OR 0.23TURNS 4/55 analyzed (7%) MMC-related serious adverse events in BNC; theoretical long-term DNA-damage concern[1][8][15]
Paclitaxel DCB (Optilume)Balloon-coatedMicrotubule stabilization → antiproliferativeROBUST III RCT + 3-y; TURNS real-world71% freedom from reintervention at 3 yUS label: adult male anterior ≤3 cm; guideline evidence best for recurrent bulbar <3 cm; repeat-use uncertainty[18][20]
Triamcinolone (intralesional)SubmucosalAnti-inflammatory + anti-collagenZhang 2014 meta; later local-steroid analysis summarized by EAU 2026Zhang: longer time to recurrence without significant rate reduction; later topical/injectable pooled trials: RR 0.67 (95% CI 0.49–0.90), low certaintyEAU weak recommendation: intralesional injections only in clinical trials; see Intralesional corticosteroids[35][36]
HA/CMCIntraluminal instillationBiophysical anti-adhesionChung 2013a post-EIU and 2013b post-TURP RCTsPost-EIU recurrence through 24 wk: 5/53 (9.4%) vs 11/48 (22.9%) among completers; post-TURP new stricture: 1/80 vs 7/81 among completersNot a pharmacologic antifibrotic; instillation technique[23][24]
PRPIntralesionalGrowth factors; preclinical healing rationaleTwo small randomized studiesRezaei: 9.09% vs 26.82% recurrence at 12 mo; Choudhury: Qmax 17.34 vs 11.39 mL/s at 6 mo (PRP plus OIU vs OIU alone; 32 per arm), without a recurrence endpointRezaei abstract/guideline discrepancy in 24-mo p value; Choudhury durability unknown[28][39]
TamoxifenOralTGF-β1 inhibition in a rat renal-fibrosis modelOne small no-adjunct RCT in Pang (30 treated)Limited single-trial versus-control recurrence evidenceGynecomastia, GI[1][29]
CaptoprilIntraluminalACE inhibitor → TGF-βn = 37 clinicalSignal present61% pruritus — poorly tolerated[1]

Evidence Summary​

Indication / agentEvidence levelKey source
Pooled adjuncts to DVIU/dilation in menThirteen RCTs (859 men) across different agents and recurrence definitions; high risk of biasPang 2021[1]
MMC for urethral strictureSystematic review (Pang: RCT meta-analysis, high risk of bias; Irdam: four small studies in the full-text analysis (abstract reports three studies and 311 patients)) + single RCTIrdam 2019[9]; Mazdak 2007 RCT[8]; Farrell 2017[10]
MMC for BNC / VUASLevel 2–3 (retrospective multi-inst)Rozanski 2021[13]; Vanni 2011[12]; Sourial 2017[14]; TURNS cautionary[15]
Paclitaxel DCBLevel 1 (RCT)ROBUST III[18]; 3-year extension[20]; real-world TURNS[21]
HA/CMCLevel 1 (RCTs)Chung 2013a[23]; Chung 2013b[24]
PRPLevel 1 (two small randomized studies with different endpoints)Rezaei 2019: 12-month recurrence[28]; Choudhury 2026: six-month Qmax[39]
Paclitaxel first-lineOngoingFIRST-CARE protocol 2026[22]

Clinical Positioning​

  • Do not treat a favorable MMC meta-analysis as a routine-use recommendation. EAU advises intralesional post-DVIU agents within clinical trials and specifically cautions against posterior MMC outside trials.[36]
  • TURNS reported serious tissue injury in 4/55 analyzed bladder-neck contracture patients (7%; 55/66 treated had ≥3 months of cystoscopic follow-up). Three required or were planning cystectomy or diversion. Radiation and extravasation concerns deserve explicit consent, as does the EAU-listed risk of de novo or worsened incontinence after endoluminal treatment of VUAS or bladder-neck stenosis.[15][36]
  • DCB evidence is stronger for a defined recurrent bulbar population. AUA 2023 advises offering urethroplasty instead of repeated endoscopic treatment after failed dilation or DVIU for recurrent anterior strictures ; it also says surgeons may use dilation or DVIU with a DCB for recurrent bulbar strictures <3 cm . ROBUST III compared DCB with standard endoscopy, not urethroplasty. The broader FDA anterior-stricture label is not the same as the AUA selection recommendation. See the device companion for exact labeling, contraindications and contraception.[3][18][20]
  • HA/CMC and PRP remain investigational stricture adjuncts. Two small randomized PRP studies with different endpoints: Rezaei reported 12-month recurrence, whereas Choudhury measured six-month flow rather than recurrence.[23][24][28][39]
  • FIRST-CARE is ongoing evidence development.[22]

See Also​

References​

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2. Jacobs ME, de Kemp VF, Albersen M, de Kort LMO, de Graaf P. "The use of local therapy in preventing urethral strictures: a systematic review." PLoS One. 2021;16(10):e0258256. doi:10.1371/journal.pone.0258256

3. Wessells H, Morey A, Souter L, Rahimi L, Vanni A. "Urethral stricture disease guideline amendment (2023)." J Urol. 2023;210(1):64–71. doi:10.1097/JU.0000000000003482

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11. Farrell MR, Sherer BA, Levine LA. "Visual internal urethrotomy with intralesional mitomycin C and short-term clean intermittent catheterization for the management of recurrent urethral strictures and bladder neck contractures." Urology. 2015;85(6):1494–1499. doi:10.1016/j.urology.2015.02.050

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13. Rozanski AT, Zhang LT, Holst DD, et al. "The effect of radiation therapy on the efficacy of internal urethrotomy with intralesional mitomycin C for recurrent vesicourethral anastomotic stenoses and bladder neck contractures: a multi-institutional experience." Urology. 2021;147:294–298. doi:10.1016/j.urology.2020.09.035

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15. Redshaw JD, Broghammer JA, Smith TG, et al. "Intralesional injection of mitomycin C at transurethral incision of bladder neck contracture may offer limited benefit: TURNS Study Group." J Urol. 2015;193(2):587–592. doi:10.1016/j.juro.2014.08.104

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18. Elliott SP, Coutinho K, Robertson KJ, et al. "One-year results for the ROBUST III randomized controlled trial evaluating the Optilume drug-coated balloon for anterior urethral strictures." J Urol. 2022;207(4):866–875. doi:10.1097/JU.0000000000002346

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20. Srikanth P, DeLong J, Virasoro R, Elliott SP. "A drug-coated balloon treatment for urethral stricture disease: three-year results from the ROBUST III study." J Endourol. 2025. doi:10.1089/end.2024.0718

21. Patel HV, Erickson BA, Abbasi B, et al. "Early real-world experience with Optilume drug-coated balloon for anterior urethral strictures and posterior urethral stenoses." Urology. 2025. doi:10.1016/j.urology.2025.10.025

22. Mahdi MB, Haase RN, Sander L, et al. "Treatment of bulbar urethral strictures with Optilume drug-coated balloons in a previously untreated population (FIRST-CARE): protocol for a single-blind multicentre randomised controlled trial." BMJ Open. 2026;16(1):e103948. doi:10.1136/bmjopen-2025-103948

23. Chung JH, Kang DH, Choi HY, et al. "The effects of hyaluronic acid and carboxymethylcellulose in preventing recurrence of urethral stricture after endoscopic internal urethrotomy: a multicenter, randomized controlled, single-blinded study." J Endourol. 2013;27(6):756–762. doi:10.1089/end.2012.0613

24. Chung JH, Kang DH, Moon HS, et al. "Effects of hyaluronic acid and carboxymethylcellulose on urethral stricture after transurethral resections of the prostate for benign prostatic hyperplasia: a multicenter, single-blinded, randomized controlled study." J Endourol. 2013;27(4):463–469. doi:10.1089/end.2012.0377

25. Kim SJ, Chae HK, Nam W, et al. "Patient satisfaction and feasibility with a novel drug-injectable urethral catheter set for hyaluronic acid administration: a multicenter randomized trial." Sci Rep. 2025;15(1):1575. doi:10.1038/s41598-024-84164-y

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27. Tavukcu HH, Aytaç Ö, Atuğ F, et al. "Protective effect of platelet-rich plasma on urethral injury model of male rats." Neurourol Urodyn. 2018;37(4):1286–1293. doi:10.1002/nau.23460

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30. Uyeturk U, Gucuk A, Firat T, et al. "Effect of mitomycin, bevacizumab, and 5-fluorouracil to inhibit urethral fibrosis in a rabbit model." J Endourol. 2014;28(11):1363–1367. doi:10.1089/end.2014.0420

31. Meng W, Jiang Z, Wang J, et al. "Inhibition of urethral stricture by a catheter loaded with nanoparticle/pirfenidone complexes." Front Bioeng Biotechnol. 2023;11:1254621. doi:10.3389/fbioe.2023.1254621

32. Choi KH, Kim DK, Kim AR, Lee SR. "Prevention of urethral fibrosis induced by transforming growth factor β1 using selective WNT/β-catenin signaling inhibitors in a rat model." Int J Urol. 2022;29(7):764–771. doi:10.1111/iju.14884

33. Zheng Z, Wu Z, Li C, et al. "Enhanced immunoregulation in traumatic urethral stricture repair utilizing a glycyrrhizic-acid-infused antiswelling biogel scaffold." RSC Adv. 2025;15(18):14217–14226. doi:10.1039/d5ra02083b

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36. European Association of Urology. EAU Guidelines on Urethral Strictures: Disease Management in Males (2026), sections 6.2.3.b, 6.2.3.d and 6.3.5.a.2.c. Guideline. Accessed September 12, 2026.

37. US Food and Drug Administration. Optilume Urethral Drug Coated Balloon, PMA P210020. FDA Summary of Safety and Effectiveness Data; FDA original Instructions for Use (1111-003 Rev A), sections 2–5 and 11 and Table 1-1. Check the manufacturer IFU library for the revision in use.

38. Bryant Ranch Prepack. Tamoxifen citrate tablets, USP: US prescribing information (NDC 72162-2208-6; updated January 19, 2024). Warnings: Thromboembolic Effects of Tamoxifen Citrate. DailyMed label.

39. Choudhury S, Talukder B, Saha S, Katiyar V. "Use of autologous platelet-rich plasma in short-segment urethral stricture (a comparative study): Experience in a tertiary care hospital." Urol Ann. 2026;18(2):111–117. doi:10.4103/ua.ua_110_25

40. Hikma Pharmaceuticals USA Inc. Mitomycin for Injection, USP: US prescribing information. Revised July 2020; DailyMed version effective May 29, 2026. Label.