Oxybutynin: past, present, and future

Oxybutynin ameliorates LPS-induced inflammatory response in human bladder epithelial cells

Urinary tract infection (UTI) mainly results from bacterial infections in the urinary tract and markedly impacts the normal lives of millions of patients worldwide. The infection and damage to urethral epithelial cells is the first and key step of UTI development and is a critical target for treating clinical UTI. Oxybutynin, an agent for treating urinary incontinence, is recently claimed with protective effects on bladder ultrastructure. Our study will assess the impact of Oxybutynin on inflammation in lipopolysaccharide (LPS)-stimulated bladder epithelial cells. Bladder epithelial T24 cells were treated with 1 μg/mL LPS with or without 10 and 20 μM Oxybutynin for 24 h. Increased levels of oxidative stress (OS) biomarkers, such as reactive oxygen species, 8-hydroxy-2'-deoxyguanosine, malondialdehyde, as well as upregulated inducible nitric oxide synthase and promoted release of nitric oxide, were observed in LPS-managed T24 cells, all of which were signally suppressed by Oxybutynin. Furthermore, severe inflammatory responses, including enhanced release of cytokines, upregulated matrix metallopeptidase-2 (MMP-2) and MMP-9, and raised monocyte chemoattractant protein-1 level, were found in LPS-challenged T24 cells, which were markedly reversed by Oxybutynin. Moreover, the activated toll-1ike receptor 4/nuclear factor-κB pathway observed in LPS-managed T24 cells was repressed by Oxybutynin. Collectively, Oxybutynin mitigated LPS-induced inflammatory response in human bladder epithelial cells.

First-in-human study to assess the pharmacokinetics, tolerability, and safety of single-dose oxybutynin hydrochloride administered via a microprocessor-controlled intravaginal ring

Polymeric drug-releasing vaginal rings are useful for both local and systemic administration of drugs via the intravaginal route. Typically, they provide continuous sustained or controlled release of drug(s) over extended time periods, thereby avoiding overdose and improving adherence. This first-in-human study (EudraCT number: 2020-0050044-30) evaluated the pharmacokinetics, safety, and tolerability of a single dose of oxybutynin administered by a novel microprocessor-controlled vaginal ring (MedRing). Eight healthy female subjects received an electronically controlled single intravaginal dose of 3 mg oxybutynin hydrochloride (100 mg/mL) dissolved in 1:1 water/propylene glycol administered via MedRing. Following dosing, MedRing was kept in situ for up to 6 h. Blood samples were collected 1 h prior to oxybutynin dosing and subsequently at regular intervals post-dose for the assessment of plasma concentrations of oxybutynin and its active metabolite N-desethyloxybutynin. The results showed that MedRing efficiently administered oxybutynin via the intravaginal route, resulting in plasma oxybutynin levels comparable to orally administered oxybutynin. The mean ± standard deviation pharmacokinetic parameters for oxybutynin were C_max 5.4 ± 2.7 ng/mL, AUC_inf 34.9 ± 17.4 h ng/mL, t_1/2 8.5 ± 3.5 h and for N-desethyloxybutynin were C_max 3.9 ± 2.5 ng/mL, AUC_inf 51.1 ± 43.1 h ng/mL, t_1/2 7.7 ± 5.9 h. No serious adverse events were reported. The study demonstrates that intravaginal administration of oxybutynin hydrochloride using the MedRing device was well tolerated.

The effect of electromagnetic field on sleep of patients with nocturia

INTRODUCTION

Accumulated studies revealed that electromagnetic field can affect human brain and sleep. We explored the effectiveness of electromagnetic field [Schumann resonance (SR)] on nocturia symptoms, quality of life, and sleep in patients with nocturia.

METHODS

This is a randomized, open-label, and active-controlled study, in which 35 participants were randomized into 2 groups. Group A received oxybutynin and the SR device for 12 weeks, while the active-control group received only the medication. We followed these patients every 4 weeks with a number of questionnaires, including the Pittsburgh sleep quality index (PSQI) and Epworth sleepiness scale (ESS) for sleep, the American Urological Association Symptom Score (AUASS) for nocturia symptoms, and the Nocturia-Quality-of-Life-questionnaire (N-QOL) for quality of life. Descriptive statistics, pair t-tests, Chi-squared tests, and repeated measures were applied for data analysis.

RESULTS

No significant difference was found in the demographic data between the 2 groups. The AUASS, N-QOL, PSQI, and ESS total scores were significantly improved in the SR-sleep-device group (P < .001, P = .005, P < .001, P = .001) after treatment, but no significant change was found in the active-control group. Several variables of AUASS in the SR-sleep-device group were significantly improved, especially streaming and sleeping (both P = .001), and subjective sleep quality and sleep efficiency also demonstrated significant improvement (both P < .001).

CONCLUSIONS

Our study revealed that electromagnetic field (SR) as an add-on can improve not only sleep and quality of life but also nocturia symptoms in patients with nocturia. These findings suggest that SR can be effective for sleep disturbance secondary to physical disease, which can be a new application of the electromagnetic field.

Catheter-Related Bladder Discomfort: How Can We Manage It?

The urethral catheter is used in various clinical situations such as diagnosing urologic disease, urine drainage in patients after surgery, and for patients who cannot urinate voluntarily. However, catheters can cause numerous adverse effects, such as catheter-associated infection, obstruction, bladder stones, urethral injury, and catheter-related bladder discomfort (CRBD). CRBD symptoms vary among patients from burning sensation and pain in the suprapubic and penile areas to urinary urgency. CRBD significantly reduces patient quality of life and can lead to several complications. CRBD is caused by catheter-induced bladder irritation due to muscarinic receptor-mediated involuntary contractions of bladder smooth muscle and also can be caused by mechanical stimulus of the urethral catheter. Various pharmacologic studies for managing CRBD, including antimuscarinic and antiepileptic agents and botulinum toxin injections have been reported. If urologists can reduce patients’ CRBD, their quality of life and recovery can improve.

Cognitive Function and Urologic Medications for Lower Urinary Tract Symptoms

Special considerations should be made when selecting medications for the treatment of lower urinary tract symptoms (LUTS) in older patients especially those over 65 years old. This review summarizes the relationship between current treatments for LUTS and cognitive impairment. Although the recently reported association between dementia and tamsulosin is debatable, the effects of α-blockers and pharmacokinetics are not reported in this context. Five-alpha reductase inhibitors appear to affect mood. However, the association between the development of dementia and cognitive impairment is unlikely. Anticholinergic agents, other than trospium, fesoterodine, and imdafenacin have a relatively high distribution in the central nervous system. In particular, oxybutynin is reported to cause cognitive impairment. Several animal studies on the blood-brain barrier permeability of oxybutynin support this. Therefore, care must be taken when they are used in older patients (65 years and older). Beta-3 agonists are an alternative to, or may be used in combination with, anticholinergic drugs for patients with an overactive bladder (OAB). Several phase 2 and 3 clinical studies report high tolerability and efficacy, making them relatively safe for OAB treatment. However, there is a possibility that cognitive function may be affected; thus, long-term study data are required. We have reviewed studies investigating the correlation of urologic medications with cognitive dysfunction and have provided an overview of drug selection, as well as other considerations in older patients (65 years and older) with LUTS. This narrative review has focused primarily on articles indexed in PubMed, Google Scholar, Scopus, and Embase databases. No formal search strategy was used, and no meta-analysis of data was performed.

The clinical pharmacology of the medical treatment for overactive bladder in adults

INTRODUCTION

Overactive bladder is a prevalent symptom complex that affects the patient's quality of life. Any disruption between the neuronal micturition pathway can lead to bladder overactivity. Neurogenic causes, myogenic causes, aging, bladder outlet obstruction, sex, and psychological factors are some of the factors contributing to bladder overactivity. The complaint of any symptoms of OAB, which is highly prevalent and affects overall QOL, often needs therapeutic interventions. When conservative therapy methods fail, the addition of medications is recommended. The most commonly used agents for the treatment of OAB are antimuscarinic drugs. New classes of drugs, such as beta-3 agonists, have enriched our pharmacologic armamentarium.

AREAS COVERED

In this review, with a special focus on oral pharmacological treatments, we discussed the definition, etiology, symptoms, diagnosis, and management of OAB.

EXPERT OPINION

OAB is a multifactorial condition with every patient presenting with a different collection of symptoms and signs. Medical therapies should be given in conjunction with behavioral therapies. Using high or low doses, flexible doses, and stopping or changing the medications are interchangeable strategies based on the level of treatment efficacy and patient satisfaction.

The development of a silicone vaginal ring with a prostaglandin analogue for potential use in the treatment of canine reproductive disorders

In veterinary medicine, vaginal rings (VRs) are rarely used. However, there are diseases of female dogs' reproductive system which represent a suitable possibility for their usage. An example of such a disease is canine pyometra which can be treated by lipophilic prostaglandin drugs, unfortunately with harmful side effects after systemic administration. The aim of the study was to prove that the matrix VR based on silicone and channel-forming substance can be successfully used as a carrier for a three-day delivery of prostaglandin E₂ (PGE₂). Based on an in-vitro release study, an optimum channel-forming substance and its concentration were selected. The results were implemented during the construction of VR from the medical grade silicone DDU-4840 with PGE₂ (5 mg). Glucose anhydrous in the 30% concentration was chosen as the most functional channel-forming substance due to synergism of osmotic activity and solubility. The DDU-VR containing PGE₂ and 30% of glucose anhydrous exhibited excellent mechanical characteristics and ensured 29% drug release through water-filled channels in first-order kinetic manner. This is eight times higher than a sample without glucose where molecular diffusion through the silicone matrix was dominating the release mechanism. Moreover, drug-free VRs were tested for mechanical resistance and the design of removal thread.

The oxybutynin abuse in adolescent case

Oxybutynin is one of the most commonly prescribed drugs in overactive bladder treatment. Because of its lipophilic structure, it crosses the blood-brain barrier and causes cognitive side effects in the central nervous system. Abuse of the drug is due to its hallucinogenic effect. In terms of substance use disorder, adolescents are one of the groups at risk. In addition to well-known addictive substances, drugs which have sedative, anticholinergic-antimuscarinic, stimulant properties and prescribed for any treatment also can be abused in adolescents with substance abuse. In this article, it is aimed to raise awareness of physicians and health workers about oxybutynin abuse because of the pharmacodynamic characteristics of the drug and its effects on the central nervous system. The health professionals should therefore prescribe this drug with more attention and follow-up those patients.

Basic and clinical aspects of antimuscarinic agents used to treat overactive bladder

Antimuscarinic agents are now widely used as the pharmacological therapy for overactive bladder (OAB) because neuronal (parasympathetic nerve) and non-neuronal acetylcholine play a significant role for the bladder function. In this review, we will highlight basic and clinical aspects of eight antimuscarinic agents (oxybutynin, propiverine, tolterodine, solifenacin, darifenacin, trospium, imidafenacin, and fesoterodine) clinically used to treat urinary dysfunction in patients with OAB. The basic pharmacological characteristics of these eight antimuscarinic agents include muscarinic receptor subtype selectivity, functional bladder selectivity, and muscarinic receptor binding in the bladder and other tissues. The measurement of drug-receptor binding after oral administration of these agents allows for clearer understanding of bladder selectivity by the integration of pharmacodynamics and pharmacokinetics under in vivo conditions. Their central nervous system (CNS) penetration potentials are also discussed in terms of the feasibility of impairments in memory and cognitive function in elderly patients with OAB. The clinical aspects of efficacy focus on improvements in the daytime urinary frequency, nocturia, bladder capacity, the frequency of urgency, severity of urgency, number of incontinence episodes, OAB symptom score, and quality of life (QOL) score by antimuscarinic agents in patients with OAB. The safety of and adverse events caused by treatments with antimuscarinic agents such as dry mouth, constipation, blurred vision, erythema, fatigue, increased sweating, urinary retention, and CNS adverse events are discussed. A dose-dependent relationship was observed with adverse events, because the risk ratio generally increased with elevations in the drug dose of antimuscarinic agents. Side effect profiles may be additive to or contraindicated by other medications.

Delivery methods for drugs used in the treatment of overactive bladder

INTRODUCTION

Overactive bladder affects a significant portion of the population and results in prescribing of numerous medications for its treatment. Traditional drug delivery systems used in therapy are associated with multiple commonly reported side effects. Adherence rates with use of these medications are low. It is likely that low adherence rates with the use of these drugs are due in some part to drug side effects. It is therefore important that alternate methods for drug delivery be explored to reduce side effect profiles and improve patient compliance.

AREAS COVERED

This article addresses the various forms of drug delivery for overactive bladder medications, focusing on those currently in use. Newer systems of drug delivery are also discussed. Through thorough review of research data, randomized trials and meta analyses, drug delivery systems were evaluated.

EXPERT OPINION

EXPERT OPINION favors the use of the transdermal patch and recognizes the necessity for further research and development of other delivery methods. The patch delivery method offers the most effective means of treating symptoms and minimizing drug related adverse side effects leading to treatment discontinuation. Development of OAB medications aimed at alternate receptor targets has the potential to facilitate the creation of new treatment methods to compete with the current standard of care used in OAB treatment.

Novel targeted bladder drug-delivery systems: a review

The objective of pharmaceutics is the development of drugs with increased efficacy and reduced side effects. Prolonged exposure of the diseased tissue to the drug is of crucial importance. Drug-delivery systems (DDSs) have been introduced to control rate, time, and place of release. Drugs can easily reach the bladder through a catheter, while systemically administered agents may undergo extensive metabolism. Continuous urine filling and subsequent washout hinder intravesical drug delivery (IDD). Moreover, the low permeability of the urothelium, also described as the bladder permeability barrier, poses a major challenge in the development of the IDD. DDSs increase bioavailability of drugs, therefore improving therapeutic effect and patient compliance. This review focuses on novel DDSs to treat bladder conditions such as overactive bladder, interstitial cystitis, bladder cancer, and recurrent urinary tract infections. The rationale and strategies for both systemic and local delivery methods are discussed, with emphasis on new formulations of well-known drugs (oxybutynin), nanocarriers, polymeric hydrogels, intravesical devices, encapsulated DDSs, and gene therapy. We give an overview of current and future prospects of DDSs for bladder disorders, including nanotechnology and gene therapy.

Investigating detrusor muscle concentrations of oxybutynin after intravesical delivery in an ex vivo porcine model

Intravesical oxybutynin is highly effective in the treatment of overactive bladder. Traditionally the mechanism of action was explained by antagonism of muscarinic receptors located in the detrusor, however evidence now suggests antimuscarinics may elicit their effect by modifying afferent pathways in the mucosal region. This study aimed to investigate the bladder wall distribution of oxybutynin in an ex vivo setting providing tissue - layer specific concentrations of drug achieved after intravesical delivery. Whole ex vivo porcine bladders were intravesically instilled with 0.167 mg mL(-1) oxybutynin solution. After 60 min, tissue samples were excised, serially sectioned parallel to the urothelial surface and extracted drug quantified. Drug distribution into the urothelium, lamina propria and detrusor was determined. Oxybutynin permeated into the bladder wall at a higher rate than other drugs previously investigated (apparent transurothelial Kp = 1.36 × 10(-5) cm s(-1) ). After 60 min intravesical instillation, concentrations achieved in the urothelium (298.69 μg g(-1) ) and lamina propria (43.65 μg g(-1) ) but not the detrusor (0.93 μg g(-1) ) were greater than reported IC50 values for oxybutynin. This work adds to the increasing body of evidence suggesting antimuscarinics elicit their effects via mechanisms other than direct inhibition of detrusor contraction.

Are we shortchanging frail older people when it comes to the pharmacological treatment of urgency urinary incontinence?

Overactive bladder and urgency incontinence are common and distressing conditions in older people, for which the first-line pharmacological treatment is a bladder antimuscarinic agent. Of these, oxybutynin is often recommended in guidelines, but is associated with a higher incidence of adverse drug effects, and in particular has been suggested to have deleterious cognitive effects. Despite this, guidelines often suggest oxybutynin as first-line treatment, and insurance based healthcare systems often require oxybutynin to be used as a first-line therapy and fail before reimbursement for the cost of newer anticholinergics is authorised. We reviewed the literature of bladder antimuscarinics in older adults, using the headings overactive bladder, urinary frequency, urgency, urge, oxybutynin, antimuscarinic, older, older people, and frail. In general, oxybutynin had a similar efficacy to other anticholinergic drugs, but a higher incidence of adverse drug events, in particular significant yet unnoticed cognitive impairment. We conclude that oxybutynin should not be used in frail older people.

Fesoterodine fumarate and the oxybutynin ring for the treatment of urinary incontinence in women

INTRODUCTION

Urinary incontinence (UI) is a prevalent condition among women of all ages. It can have a significant negative impact on women's quality of life causing not only physical but also psychological distress.

AREAS COVERED

This article aims to provide a review of the pharmacology, efficacy, safety and tolerability of fesoterodine fumarate (the newest anticholinergic launched in the UK) and the oxybutynin vaginal ring (the newest route of drug delivery in development) in the treatment of urgency UI.

EXPERT OPINION

Fesoterodine is now a well-established treatment option; however, as with all oral anticholinergic agents its use is hindered by side effects. The efficacy of the oxybutynin ring has only been demonstrated in small studies. Larger clinical trials assessing the efficacy, tolerability and acceptability are required before appropriate recommendations can be made.

The vagina as a route for drug delivery: a review

Overactive bladder (OAB) syndrome has a significant deleterious impact on quality of life. After conservative therapy and bladder retaining, antimuscarinic drugs remain the mainstay of OAB management. Oral therapy is associated with frequent side effects, leading to the development of alternative agents and formulations or the use of novel routes of drug administration, such as the vaginal route. The vagina is often ideal for drug delivery because it allows the use of lower doses, maintains steady drug administration levels, and requires less frequent administration than the oral route. With vaginal drug administration, absorption is unaffected by gastrointestinal disturbances, there is no first-pass effect, and use is discreet. The aim of this review is to provide a background overview of vaginal development, anatomy, and physiology and the effect this has on the use of this route for both local and systemic drug delivery, with special reference to OAB management. Vaginal therapy continues to be an underused route of drug delivery. Vaginal administration allows nondaily, low, continuous dosing, which results in stable drug levels and may, in turn, achieve a lower incidence of side effects and improve patient compliance. These benefits must be balanced against inherent patient or physician bias against using this route and the need to overcome cultural, personal, and hygiene-related barriers to this form of therapy. More sophisticated and programmable vaginal rings are being developed for systemic delivery of therapeutically important macromolecules, such as antimuscarinic therapy in OAB management.