Can Sildenafil Help Overactive Bladder? New Research Offers Hope
"A new study explores how sildenafil, commonly known as Viagra, could ease overactive bladder symptoms by targeting nitric oxide deficiency."
Overactive bladder (OAB) affects millions, leading to frequent urination and a constant urge to go. While medications exist, researchers are always looking for new ways to manage this condition. Interestingly, drugs like sildenafil, typically used for erectile dysfunction, have shown potential in treating OAB.
Sildenafil belongs to a class of drugs called phosphodiesterase-5 (PDE5) inhibitors. These drugs work by increasing blood flow, but they also impact smooth muscle function. Since the bladder and urethra contain smooth muscle, scientists have been investigating whether sildenafil could help improve bladder control.
One key factor in bladder function is nitric oxide (NO). NO helps relax smooth muscles, allowing the bladder to fill and empty properly. When NO levels are low, the bladder can become overactive. This study, originally published in the "International Brazilian Journal of Urology," explores whether sildenafil can improve OAB symptoms in rats with nitric oxide deficiency.
How Common OAB Is
Bothersome overactive bladder symptoms affect an estimated 30 million adults in the United States, according to a review of OAB treatments. Symptoms include frequent urination and a persistent urge to urinate; the article describing sildenafil’s potential role attributes them to bladder muscles contracting too often. The 2024 Urologic Diseases in America Annual Data Report notes that AUA and AUA/SUFU guidelines recommend urinalysis as part of the initial diagnostic process.
Guided Treatment Choices
The 2024 AUA/SUFU clinical practice guideline provides evidence-based guidance for evaluating and treating idiopathic OAB, including an approach to selecting options through shared decision-making. A 2021 guideline summary describes OAB as causing a sudden, unstoppable need to urinate and affecting physical, social, and emotional functioning. A review of developing pharmacotherapies says new treatments are needed and evaluates novel drugs, combination therapy, and treatments still in development.
A Changing History of OAB Treatment
Pharmacologic treatment of urinary storage problems, including OAB, has diversified and changed over time. A 2025 review updates discussion of recommended drugs using selective reviews spanning five decades, from the 1980s to the present. A 2024 history of urgency and OAB treatment notes that the International Continence Society’s concise definitions have helped clinicians offer treatment, although the underlying causes of urgency remain multifactorial and not fully understood.
How Sildenafil Tackles Overactive Bladder in Rats
The study focused on rats with OAB induced by reducing nitric oxide levels. Researchers divided the rats into groups:
- Control group: Received normal drinking water.
- L-NAME group: Received L-NAME, a substance that inhibits nitric oxide production, in their drinking water.
- Sildenafil group: Received sildenafil intravenously.
- L-NAME + Sildenafil group: Received both L-NAME in their drinking water and intravenous sildenafil.
Early Experimental Work on Tadalafil and Sildenafil
An experimental study evaluated whether combining BRL-37344 with tadalafil could reduce OAB symptoms after detrusor overactivity was induced in mice. Other cited animal research concerns tadalafil with tamsulosin in rats with bladder outlet obstruction caused by chronic nitric oxide deficiency; its snippet reports a finding comparable to a study in which acute sildenafil administration decreased the number of MC. A separate experimental-model report says sildenafil and vardenafil had shown relaxing effects on smooth muscle in the bladder, prostate, and urethra. These findings describe preclinical work and do not establish that sildenafil treats OAB in people.
Evidence Comes from Different Conditions
A meta-analysis of 16 trials reported that men taking sildenafil were 3.57 times as likely as men taking placebo to report improved erections (95% CI 2.93–4.43); this evidence concerns erectile dysfunction, not OAB. In an OAB comparison, antimuscarinics, mirabegron, and peripheral tibial nerve stimulation had similar efficacy for reducing micturition frequency, urinary incontinence episodes, and urgency urinary incontinence episodes, and all examined interventions were efficacious compared with placebo. These findings come from different treatment questions and do not directly compare sildenafil with established OAB therapies.
The Future of Sildenafil and Overactive Bladder Treatment
This research suggests that sildenafil may have a role in managing overactive bladder, particularly when nitric oxide deficiency is a factor. By improving smooth muscle relaxation in the bladder, sildenafil could help reduce the frequency and urgency associated with OAB.
A Broader OAB Treatment Pipeline
An OAB pipeline outlook published in 2026 describes developments as signaling a shift toward more tolerable, patient-friendly options and a robust worldwide pipeline for OAB management. The source characterizes OAB by urgency, frequency, and nocturia across diverse populations. A separate market forecast points to demand involving beta-3 adrenergic agonists such as mirabegron and vibegron, botulinum toxin, sacral neuromodulation, anticholinergic drugs, and non-invasive treatments. These outlooks identify broader directions in OAB care but do not specifically establish sildenafil as a future treatment.
However, it's important to remember that this study was conducted on rats. More research is needed to confirm these findings in humans and determine the optimal dosage and potential side effects of sildenafil for OAB. It’s also vital to understand if the positive effects seen in the rat study will translate to humans, and if so, for which specific OAB patients.
While further studies are necessary, this research opens up exciting possibilities for new OAB treatments. If you're struggling with OAB, talk to your doctor about available options and whether participating in a clinical trial might be right for you.